Since its founding in 2016, Elon Musk’s brain-computer interface (BCI) company Neuralink has had its moments in biotech news.

Whether it was the time Musk promised his “link” would let people communicate telepathically, or when the whole company was investigated possibly violated the animal welfare law, the hype around Neuralink means it’s often the first mental reference people have for BCI technology.

But BCIs have been kicking around for much longer than you might expect. Musk’s is just one in a growing list of companies dedicated to advancing this technology. Let’s take a look back at some BCI milestones over the past few decades, and look ahead to where they could lead us.

A growing industry

Brain-computer interfaces are devices that connect the brain to a computer so that the user can perform a certain action using its brain signals.

Many high-profile companies entered the BCI field in the 2010s backed by millions of dollars in investment. Founded in 2016, the US company Kernel began researching implantable devices, before moving to non-invasive techniques that do not require surgery.

Even Facebook tried out BCIs, with an ambitious plan to create a headset that would allow users to type 100 words per minute. But it stopped this research in 2021 to focus on other types of human-computer interfaces.

First contact

The earliest BCIs, developed in the 1970s, were relatively simple, used on cats and other animals to develop communication pathways. The first device to be implanted in a human was developed by Jonathan Wolpaw in 1991and allowed the user to control a cursor with their brain signals.

Advances in machine learning over the years paved the way for more sophisticated BCIs. These can control complex devices including robotic limbs, wheelchairs and exoskeletons. We’ve also seen devices get smaller and easier to use thanks to wireless connectivity.

Like many newer BCI devices, neural link has yet to receive clinical trial approval for its invasive implant. The latest filing with the US Food and Drug Administration had been rejected.

However, there are three notable groups conducting clinical trials worth keeping an eye on.

1. BrainGate

Founded in 1998 in Massachusetts, the BrainGate system has been around since the late 1990s. This makes it one of the oldest advanced BCI implant systems. The device is placed in the brain with microneedles, similar to the technology used by Neuralink.

BrainGate’s devices are probably the most advanced when it comes to BCI functionality. One of the wired devices offers a typing speed of 90 characters per minute, or 1.5 characters per second. a study published in January published results of data collected over 17 years from 14 participants.

During this time, there were 68 cases of “side effects,” including infection, seizures, surgical complications, irritation around the implant, and brain damage. However, the most common occurrence was irritation. Only six of the 68 incidents were considered “serious”.

In addition to communication applications, BrainGate has also achieved self-powered robot control.

2. UMC Utrecht

The University Medical Center in Utrecht, the Netherlands, was the first to achieve fully wireless implanted BCI technology that patients could take home.

The device uses electrocorticography-based BCI (ECoG). Electrodes in the form of metal discs are placed directly on the surface of the brain to pick up signals. They connect wirelessly to a receiver, which in turn connects to a computer.

Participants in one clinical trial which ran from 2020 to 2022 could take the device home and use it every day for about a year. It allowed them to control a computer screen and type at a speed of two characters per minute.

Although this typing speed is low, future versions with more electrodes are expected to perform better.

3. Sync (originally SmartStent)

Sync was founded in 2016 in Melbourne, Australia. In 2019, it became the first company to be approved for clinical trials in Australia. Then, in 2020, it became the first company to receive FDA approval to conduct clinical trials of a permanently implanted BCI – eventually doing so with a American patient this year.

Synchron’s very small ‘stentrode’ can be implanted with a minimally invasive procedure. Sync

Synchron’s approach is to bypass whole brain surgery by using blood vessels to implant electrodes in the brain. This minimally invasive approach is similar to other stent procedures routinely performed in clinics.

Synchron’s device is placed in the brain near the area that controls movement, and a wireless transmitter is placed in the chest. This transmitter then transfers brain signals to a computer.

Initial clinical results have shown no adverse effects and a functionality of 14 characters per minute using both the BCI and eye tracking. No results were reported for BCI use alone.

While the efficiency of the device can be improved, Synchron’s approach means it is leading the way in achieving a low barrier to entry. By avoiding the need for full brain surgery, it helps bring BCI implantation closer to a day procedure.

The benefits must outweigh the risks

The history of BCIs reveals the enormous challenges associated with the development of this technology. These are compounded by the fact that experts still don’t fully understand the connections between our neural circuits and thoughts.

It’s also unclear which BCI features consumers will prioritize to move forward, or sign up for. Not everyone will be happy to opt for invasive brain surgery the systems those that don’t need it collect “noisy” data that isn’t as efficient.

Electroencephalogram-based (EEG) BCIs do not require surgery, but because they are less invasive, they are also less effective. Answers will emerge as more devices are approved for clinical trials and research on the results is published.

Importantly, developers of these technologies should not rush through trials. They have a responsibility to be transparent about the safety and efficacy of their devices and to report it openly so that consumers can make informed decisions.