Elon Musk's claim his brain-machine interface startup Neuralink implanted a device in its first live human subject comes after the company navigated a rigorous approval process, with some bumps along the way.

Why it matters: If successful, Neuralink says its technology will allow users to operate devices like a phone using only brainpower, and could be used to treat neurological diseases. While the technology is unproven, starting human testing is a major step.

Driving the news: Musk posted on X that the company's first human subject received a brain implant on Sunday and was "recovering well."

• He claimed that initial results "show promising neuron spike detection," referring to the device detecting the subject's neural activity.
• The announcement, which has not been independently verified, came months after Neuralink received FDA approval to begin human clinical trials.
• The company said in a blog post that the purpose of the first human trial is to evaluate the safety of the device and the surgical robot that implants it, as well as testing its ability to read and decode neural activity.

Reality check: Musk has a history of over-promising when it comes to milestones for his companies, and little additional information is available about the status of the ongoing trial.

• But while Musk's announcement drew social media jibes highlighting well-publicized tech failures at Tesla and SpaceX, the FDA has rigorous standards in place to protect human subjects in medial trials.

What is Neuralink?

Musk founded the company along with a team of neuroscientists in 2016 with the mission of developing and marketing an implantable brain–computer interface device.

• The device, in its current design, is "cosmetically invisible," consisting of a lithium battery that can be charged wirelessly, small computer chips and other electronics, according to the company.
• The device would be implanted into the brain by a surgical robot that looks like a sewing machine and has cameras, sensors and a needle that's thinner than a human hair.

Neuralink has marketed the device as being able to treat neurological diseases and injuries.

• However, Musk has also described the company as a means of augmenting human biology and merging it with machines and artificial intelligence.
• Musk on Monday also announced that Neuralink's first product would be called "Telepathy," which "enables control of your phone or computer, and through them almost any device, just by thinking."
• "Initial users will be those who have lost the use of their limbs. Imagine if Stephen Hawking could communicate faster than a speed typist or auctioneer. That is the goal," he added.

Does the device work?

Neuralink has claimed that the implant can read brain activity, which can be used to manipulate other devices.

• While that has yet to be proven in humans, Neuralink publicly demonstrated the device and software in a nine-year-old macaque named Pager in 2021.
• According to the company's demonstration, the primate was able to manipulate a computer cursor to a target with only its brain signals. If it hit the target, it received a squirt of banana smoothie.
• Pager was also shown playing a version of the arcade game Pong, apparently using only its mind.

Why have Neuralink and its device been criticized?

The company has been accused of mistreating animals and potentially risking human exposure to infectious pathogens through contaminated hardware.

• Internal staff complaints alleged that animal testing was rushed, resulting in needless suffering and animal deaths, prompting an investigation from the Department of Agriculture, according to Reuters.
• Records reviewed by Reuters in 2022 indicated that the company had killed 1,500 animals since 2018, including 280 sheep, pigs and monkeys. Animals are routinely used in medical research, and many tests involve "terminal procedures."
• Neuralink defended its treatment of animals in multiple blog posts, while Musk has claimed no monkey has died as a result of the implant.

How did Neuralink get FDA approval?

Neuralink announced in May 2023 it received FDA approval to begin testing its brain-implant technology in humans.

• On Tuesday, the FDA confirmed approval had been granted but told Axios it could not disclose any information about studies related to new devices.
• The company had been denied an "investigational device exemption" (IDE) to begin human testing earlier in 2023 for reasons that were not disclosed.

In order for new medical devices like Neuralink's implant to become marketable, they must first get several forms of FDA approval and go through a gauntlet of tests to ensure they are safe and effective.

• For Neuralink, there are likely three devices being submitted for regulation: the implant, the surgical robot and the software.
• To begin with, the product has to be defined as a medical device used to treat certain medical conditions.
• The risks associated with the device then have to be classified. For Neuralink's implant, it's likely among "Class III devices," which are considered to be high-risk and require additional regulatory steps.

The next step is to apply for an IDE to begin human trials.

• The application requires a report of prior experiments, like tests on animals, a description of how the device is designed and manufactured and a plan for how the company will carry out the human trials and what exactly it is seeking to test.
• If the FDA determines a trial is not being conducted as described in the application or is causing serious harm to participants, it can pause or terminate a clinical trial at any time.

The final and most stringent step before a Class III device can be approved for sale is the premarket approval (PMA) process.

• FDA scientists rigorously scrutinize trial results and other elements of the application before clearing any device to go to market.
• Even if a device is approved, the FDA may exclude some patient groups, such as children, or limit its use to patients with distinct medical needs.

Are other companies working on similar devices?

Research on brain implants and related technologies has been ongoing for decades, and many people already use neural implants that are similar to pacemakers to treat seizures that do not respond to medications.

• Several other companies are working on brain-machine interfaces. One, Synchron, received FDA approval for human trials in 2021.
• The Pentagon also previously devoted funding to explore the potential military applications of the technology.

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