When sci-fi becomes reality: could brain-machine interfaces be right around the corner?

For most of human history, the field of engineering has been seen as distinct from biological and neural science. Living tissue has a quality of its own, and cannot easily interact with an electromechanical device. This perspective is now in flux. Within a matter of months, hardware that has been conceived by man in the laboratory will begin to converse with our cerebral cortex.

The idea of a brain-machine interface has been around for at least 50 years. It’s a common staple of a certain kind of science fiction novel and has already made the transition to science fact in research laboratories all over the world. Scientists working in this field have even conjured up a new name to describe their collective vision: transhumanism. They plan to take us on a journey into the future, and it is a future in which the frailty of human tissue will be augmented by computer science.

It’s a concept so intoxicating that it has attracted the attention (and funding) of several of the world’s biggest tech barons including Bill Gates, Elon Musk and Jeff Bezos. These billionaire investors have access to the kind of research funds that would put most European governments to shame. As forward-thinking and driven individuals, they have the option of directing their resources to specific research topics including projects that more mainstream fund managers might have dismissed as high risk – whether or not this level of investment will result in an increased rate of progress.

Elon Musk – perhaps the most famous tech investor – is the majority shareholder in the Neuralink Corporation. Neuralink was set up to develop implantable brain-computer interfaces ie electronic devices that might be surgically inserted into a person’s head in a bid to set up a data link between their nervous system and an external computer.

Like so many other forward-thinking tech companies, Neuralink was established on the US west coast. Its offices in San Francisco are reported to employ around 90 people, and in the space of just a few years it has already filed a number of patents; among them, a “sewing machine-like” device designed to implant very thin threads into the brain.

In case you hadn’t spotted it, I should probably mention that this isn’t going to be easy. An individual nerve cell is an incredibly small thing. The wires that the current generation of scientists are proposing to insert into the brain are huge, cumbersome devices in comparison to the delicate network of tiny neurons that make up our brains. In practice, they’re looking to detect clusters of electrical discharge in groups of neurons close to the point of insertion of each wire.

To what extent will this help with our understanding of the human brain? That remains uncertain. As things stand, we don’t even understand the language in which the human brain functions – although we do have an understanding of much of the motor and sensory cortex and the pathways by which instructions are transmitted to our muscles.

If you’re fan of the Matrix movies, you may remember the sockets many characters have in the back of their skulls. With this kind of electronic interface on hand, we ought to be able to plug a person into a laptop and download their life story with relative ease. Worse still, we might want to send messages in the opposite direction and insert a few thoughts of our own, just to give them a more righteous path to follow.

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This idea of alternative thought insertion was briefly alluded to in the third act of the recent James Bond epic, No Time to Die. The evil mastermind at hand had developed nano-scale implants that he planned to insert by contact with the skin. Once inside the victim’s body, these could be used to alter someone’s personality, even to make them obedient or more readily sensitive to suggestion. Perhaps predictably, this latest attempt at world domination comes to nothing. Bond manages to dispose of the evil research lab with a spectacular explosion in the finale.

But this is far-fetched. Right? In the real world, how far off we are from exactly this nightmare?

The brain and spinal cord are particularly difficult tissues to study. In practice, we know far more about the central nervous system of a rabbit than we do about that of a human, and the reason for this is acutely obvious: most brain and spinal cord experiments end in sacrificing the animal under investigation, and rabbits are relatively easy to dispose of. Upgrading this work to the human model is going to be more difficult, if for no other reason than because of the ethical issues involved.

Neuralink claims that it is likely to start human trials in 2023. At a recent press conference, Elon Musk described its new device as a “Fitbit in your brain”.

There are reports that Musk’s company was set up on a budget of $100 million dollars. In the meantime, the scientists at Neuralink have slaughtered a number of macaque monkeys, which is the most commonly used animal model for this kind of work. The Americans are the biggest users of macaques in the world, and traditionally they have obtained their macaques from China. More recently they’ve been sourced through Cambodia, largely due to the Covid-19 crisis. Thus far, the staff at Neuralink are reported to have killed 1,500 animals, including pigs, sheep and monkeys.

These numbers have to be seen in perspective. Worldwide, research scientists kill around 100 million laboratory animals a year, and euthanasia is hardly unique to Neuralink or indeed to neural science as a whole. It’s been suggested that its work may offer treatments for conditions such as paralysis, Parkinson’s disease, Alzheimer’s and many more. It sounds exciting, but it isn’t entirely altruistic. If a cure can be found for such conditions, people everywhere will be willing to pay good money to free themselves from suffering.

On the downside, it should be remembered that neural science is a particularly stubborn field. Many years ago, the Germans invented a device for monitoring brain waves called the EEG. It’s basically the equivalent of the ECG on the heart and picks up electrical signals from the scalp. At the time, there was much excitement about this device. There were some scientists who thought that it might represent an interface between hard science and a much more ephemeral subject like psychology. These people would soon be disappointed.

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The EEG is limited because it seeks to pick up an electrical signal from the skin. In practice, the signal has already been muffled by the skull and surrounding soft tissue. Some of the more recent research has seen scientists seek to actually lay a chip underneath the skull and in direct contact with the brain. Using the Neuralink system, about 1,500 tiny electrodes would then be pressed down onto the brain tissue in a bid to detect electrical activity (if that sounds like a lot, they’re said to only be about four to six micrometers in diameter). This approach will require scientists to open the skull using neurosurgical techniques; not an experiment I’d ever volunteer for myself.

At the other side of the North American continent, Bill Gates and Jeff Bezos have both invested significant sums in the New York-based company Synchron, another tech start-up with a plan to develop its own brain-computer interface.

One problem with obtaining high-quality data from the brain is access. Synchron is planning to gain access using some of the large blood vessels in the neck, rather than by opening the skull itself. In principle, it could try to pick up motor intent from a human brain and transmit it to an external electronic device. Once there, it could be decoded, amplified and passed on to the muscles in the legs. Either that or a mechanical exoskeleton of the type that are now under development. This sort of tech could circumvent the damaged nerve pathways in a quadriplegic patient and enable the patient to climb out of their wheelchair and walk again.

It would be foolish to underestimate the ability of men like Bezos, Musk and Gates to raise capital or indeed to identify areas that are ripe for investment. At the same time, it has to be understood that much of the work involved has been contaminated by hype. The tech barons seem to thrive on publicity, and few if any of them have any real knowledge or experience of medical science. Musk and others in the tech sector have a habit of blurring the boundaries between science fiction, blue sky thinking and real engineering. That isn’t to say that what they’re doing isn’t laudable, but the gap between where we are now and where we would have to be to “cure” some of the illnesses under consideration is huge.

In addition, there are awkward ethical and legal issues ahead. Supposing a company patents a device to treat schizophrenia. If that implant is then inserted into the brain of person who has been convicted of a serious offence, can they then be released back into society? If his previous conviction stemmed from an altered mental state conjured up by a specific disease, and that disease has now been cured, surely they can be released? But if they are released and go on to re-offend, who then will be responsible for the second offence? There’s a similar emergent issue with the insurance policy on self-driving cars and, thus far, no one’s really come up with a simple way out of it.

Elsewhere in the world, there are many other gifted and brilliant figures who have been toiling in this area for decades. Some of them are more than sceptical of the tech barons who think they can simply sign a cheque and transform these fields in a few spare hours.

When peripheral nerves are damaged, they are incredibly difficult tissue to repair and reconstruct. In fact, the only thing harder to repair than peripheral nerves are nerves within the central nervous system (ie the brain and spinal cord) which are almost completely recalcitrant to repair and recovery.

As long ago as the 1920s, a German neurosurgeon opened the back of the skull and looked down upon the exposed occipital cortex of the brain. He then touched the exposed brain with an electrode and applied a small electrical charge. The patient – who was conscious – reported seeing a white spot in his mind. By modern standards this was a crude procedure, but it was also the first time that we realised that it might be possible to send a message directly into the human brain using an electrical current. A hundred years later our technology is still clumsy, but it’s improving all the time.

In fact, blindness is one area where science has made some progress and there are real devices on the market. It’s relatively easy to stimulate the occipital cortex (the tissue at the very back of the brain) where visual imagery from the eye is normally fed via the optic nerve. In people who have sustained damage to their retina, we may be able to feed visual information to the occipital cortex from a picture taken by a digital camera either in the eye socket itself or in some sort of attached spectacle.

Current-day implants can create an image that is 10 by 10 pixels in the mind of a blind person, leaving them far better equipped to find their way around. There are around 40 million blind people in the world, and if you are one of them you might regard this kind of work as especially exciting. In years to come, it may be possible to achieve a much higher resolution. Some researchers are already talking about incorporating night vision into the cameras.

Transhumanism might sound like science fiction now, but some of the advances involved are just around the corner.