The vast promise and harrowing pitfalls of neural implants

Neuralink, founded by Elon Musk, has huge ambitions. Musk isn’t the only billionaire dabbling in this space, though. Others who have put money into neural implants and brain-computer interfaces include Bill Gates, Mark Zuckerberg and Jeff Bezos.

Our brains and bodies work together through a network of neurons that carry messages and commands via electrical impulses. With experiment and guesswork, and using scans that record and analyse brain activity, researchers have developed an understanding of which parts of the brain processes which types of inputs. Neural implants can help in many cases of neural damage or illness.

There are several types of neural implants, each designed for a narrow set of purposes. Some monitor people with epilepsy; others help paralysed people regain mobility or connect them to computers to help them communicate. Some can even improve sight and hearing. Neural implants can also help combat Parkinson's Disease or amyotrophic lateral sclerosis (which Stephen Hawking suffered from). Even depression or schizophrenia can be mitigated via implants.

Implants can thus dramatically improve the quality of life in some cases. But Neuralink has even bigger goals. While it can help with medical conditions, its ultimate goal is to enable everyone – including healthy people – to connect seamlessly to computers. Its mission statement is to “create a generalised brain interface to restore autonomy to those with unmet medical needs today and unlock human potential tomorrow."

Neuralink has designed a brain-computer interface (BCI) called the Link along with a specialised robot that performs the delicate task of attaching it to the brain. This Link has an unusual multi-channel electrode design and has been tested on monkeys and pigs.

The company claims, “Our implant is fully implantable, cosmetically invisible, and designed to let you control a computer or mobile device wherever you go". Musk has said he plans to wear one someday and that nobody will be able to tell.

Humans with the link will be able to directly access and control devices. As computing advances and AI becomes all-pervasive, users of these implants could be at the cutting edge. This is all speculative at this point, of course, but that hasn’t stopped Musk from saying that such implants could one day be used to back up people’s thoughts and memories, thus storing their “digital souls".

While this sounds far-fetched, AI can already decode thoughts, albeit in a limited way. In a recent experiment, a research team from The National University of Singapore, Stanford University and The Chinese University of Hong Kong put volunteers inside functional magnetic resonance imaging (fMRI) machines and recorded brain activity while showing them images. They used that data to train an AI. Eventually the algorithm could guess what the brain was seeing with over 80% accuracy. It’s possible that AI running on quantum computers could store and decipher more complex thoughts in the future. If you can people’s clone bodies (already technically possible) as well as their thoughts and memories, you have a form of immortality.

Implants have already delivered astonishing results. The Braingate, a device originally developed at Brown University in collaboration with Massachusetts General Hospital and the US Department of Veterans Affairs, allows patients with tetraplegia (the inability to move all four limbs) to control cursors, type, and control TVs. Patients paralysed by brainstem stroke could control robotic arms. In April 2021, BrainGate became the first technology to transmit wireless commands from brain to computer.

In May 2023 Nature published research describing how implants helped 40-year-old Gert-Jan Oskam, who had been paralysed from the hips down for 12 years, to stand, walk and ascend a ramp with a walker. Blackrock Neurotech plans to introduce the first commercially available BCI system next year. Synchron has FDA approval to begin clinical trials of a permanently implanted BCI, and Paradromics is also gearing up for human trials.

While implants curing deafness are almost passe, there’s also been very promising research into linking optical nerves to cameras and artificial eyes. Research on combating depression by stimulating parts of the brain via implants has also shown promise.

There are, however, several potential dangers and ethical issues here. For one, this is invasive surgery. It could cause scarring or other permanent damage. Replacing or extracting such implants is another issue. In at least two experiments, some volunteers wished to keep their implants when the experiment ended, while others didn’t. In one case, the company conducting the research went bankrupt. It isn’t easy to assign medico-legal costs to such consequences.

Also, what happens if an implant user is connected to a machine that is hacked? If Musk’s ambitions come to fruition, we could have a scenario in which an authoritarian government forces every citizen to wear an implant that records their thoughts and controls their actions. As the research progresses, more such potential issues will come to the fore.