Upgrade: technology for the human body 2.0

Following a brutal mugging, which resulted in the death of his wife, ‘Upgrade’ hero Grey Trace (Logan Marshall-Green) was left a quadriplegic. Clearly as a couple they had been comfortably well-to-do, so Trace at least had an apartment featuring all the mod cons of the fairly near future to make his life a bit easier, if not more tolerable.

Voice-activated robotics took care of his physical needs while the plethora of interfaces fortunately didn’t need physical interfacing, such was his condition. His wheelchair had a charging pad, a bit like those that currently malfunction for our phones today, and there was also an energy wall, which had no specified function other than to look more purposeful than the framed Hockney print that might occupy such a space today. Then he was offered the chance of some more advanced technical assistance.

The actual mugging took place when the autonomous car Trace was riding in was hacked and diverted into the habitat of ne’er-do-wells, who duly did the dirty on him and his missus. Between this not-so-smart transport and the smart homes, police drones and guns embedded in people’s arms, there is plenty to analyse in this film from a technology point of view, but an obvious focus is STEM, the star of the show.

STEM is a computer chip that is embedded at the base of Trace’s neck where the trauma (gun shot) occurred. Interesting that STEM looks like an old-fashioned DIL chip – the sort that is rarely used these days except in some hostile environments where a lot of shaking is going on and having the long legs that go through the printed circuit board makes them more robust. Anyway, the chip in ‘Upgrade’ appears to just be left to float in Trace’s body, so having any legs at all is really a homage to what people think electronics should look like, rather than it having a circuit to fit into. At the time of implantation it also seemed to have morphed slightly into a more bug-like, living thing.

However, nit-picking about sci-fi might be fun, but is also pointless. The big issues thrown up by the film are really concerned with how far two things could develop – one is artificial intelligence and the other is the science behind the human body as a biomechanical machine. I’m leaving the former because to explore how far ‘Upgrade’ takes AI would be a massive spoiler for those who haven’t seen the film. All I will say is that the trouble with AI is it always turns a bit naughty – it never ends well. Why does AI never crop up with a sunny disposition?

However, just as interesting is looking at the knowledge of how the body works and how it could develop in the future. In ‘Upgrade’, inserting STEM in his neck not only gives Trace back the use of his limbs, it also allows his body to move super fast, turning him into a lean mean killing machine. Finally it has its own intelligence, which entwines with Trace’s own thoughts.

The body is extraordinarily complex. It is neurons that convey electrical or chemical messages around the nervous system, either adapted for sensory (feeding messages from the periphery back to the brain) or motor (issuing instructions that the body converts to actions) applications. There are in the region of 80-100 billion neurons in the human body, and while the majority of these are going about the difficult business in the brain there are plenty scattered around the body making sure the messages are sent and received. The spinal cord has tens of millions of these neurons and is the focal point for channelling the nervous system’s messages to and from the brain, which is why damage to it affects the function of everything below it – so serious damage to the middle or lower back can result in loss of function of the legs, while damage to the spinal cord at the neck affects the arms, too.

Tom Otis, professor of neuroscience and chief scientific officer of the Sainsbury Wellcome Centre for Neural Circuits and Behaviour, is well versed in brain interface technology. In the film, STEM performs this interface function. Otis says: “Brain interfaces that bridge in a quadriplegic situation don’t exist. The most successful brain-machine interfaces that exist now are cochlear implants on the sensory side. There is also really robust R&D and devices for retinal prosthetics.”

Cochlear implants have eight channels and are stimulated by the fluid that’s moved by the ear drum. Sound is detected and the implants act as a frequency deconstructor: each of the eight sensory cells represent frequencies from the tens of hertz up to 20kHz in a young person. Those sensory cells contact to hair cells which go into the brain – if it is the hair cells that have failed they are replaced by physical wires. Otis says: “At first when getting implants people’s ability to differentiate tones and frequencies isn’t very good, but quite rapidly their brains learn to make sense of the input. So for other brain-machine interfaces, this could be an interesting factor.”

Again, going back to the nit-picking, Trace’s body performance was instant and didn’t allow for any of this learning process. Equally, muscles that are left redundant for three months suffer what is known as muscle atrophy (wastage) and would not be fighting fit instantly.

Despite the phenomenal number of physical connections that would be needed to just provide a bridging function – restoring the links – in a traumatised nervous system, Otis does not think it is impossible, although more progress has been made on devices implanted directly in the brain.  

“Devices aren’t as advanced on the output [motor] side,” he says, “but that is coming. There are companies that are seeking to patent brain-machine interfaces to bridge lesions, similar to this case [‘Upgrade’]. There are published examples of where a brain interface is being used to control a robotic arm with some dexterity.” In these cases the chip is inserted directly in the cortex area of the brain, where instructions for voluntary movement come from. It can then be used to control an exoskeleton, or part thereof.

Which brings us to the next stage of what STEM brought to Trace – lightning reflexes and superhuman strength. Otis is less convinced that this is possible: “Conceivably, with the technology we have now, that chip could bridge the lesion [in the top of the neck] and allow that person to move. If you had an exoskeleton, then you could potentially read out the signals from the brain, so you could have superhuman performance in the robotics.”

Trace, however, does not have the advantage of an exoskeleton; his equipment is the bone and muscle (apparently non-atrophised) that he was born with. Otis says: “We can say with current knowledge, the nerve impulse part is not rate-limiting for movement. A lot of it has to do with the ‘plant’ – the muscles: how long it takes for a muscle to get excited and contract, and obviously for the coordination of activation of the muscles, the things like the vestibular [sensory systems in the ear] feedback to maintain balance.

“The time it takes to send a signal from cortex to the spinal cord that you are going to throw a punch might be 3 or 4ms. The actual time from when the activity is in your brain to throwing that punch might be more like 200ms if you are a trained boxer. Then there are other thought processes, like ‘Is it the right thing to do?’, that are upstream of that.”

Irrespective of how quickly your mind decides it wants to punch the bad guy, and no matter how quickly the electrical messages are zapped through the neurons by STEM-like devices, the fundamental mechanics of the body will always be a limiting factor.

Repairing a body is also far more complicated than deploying exoskeletal features. “It is fascinating,” says Otis, “if you want to perform an activity like raising a glass or catching a ball you can measure and decipher neuron activity, and that could be transmitted to robotic arms. But if you are trying to do that with muscles then it might mean more like reconnecting 90 per cent of the neurons rather than 10 per cent. Existing brain-machine interfaces may be connected to a hundred or so neurons and the person performs a number of activities. It catalogues these movements, and then they build up a model of the code. They can do that with 100 neurons, even though each action might involve 25,000 neurons. This is particularly possible in the brain [rather than a spinal implant] as there are parts of the cortex that are dedicated to motor control.”

Just to touch on the AI aspect and its interaction with human thought processes, there is a much longer journey to go here. Firstly, STEM is implanted in the spine – is it possible for cognitive thought to reach as far as the spinal cord? “We don’t know,” admits Otis. “Could someone be daydreaming and those thoughts exist in the spine, without interfering in motor functions that are going through the spine? We just don’t know.

“If this chip was up in the frontal cortex, the hippocampus, other areas that are involved in these more cognitive phenomena, then maybe it’s conceivable – at least it’s not completely dismissible.”

The trouble is we can imagine the human body as a biomechanical machine – engineers across the ages have been able to understand and fix the most delicate things – but the creative part of the mind is still a mystery.

‘Upgrade’ is an enjoyable and thought-provoking film, but will cause the occasional wince as the bones snap. It has been on general UK release since 31 August 2018.