Ahundred electrodes are pressed tightly against my scalp and a mixture of salt water and baby shampoo is dripping down my back. The goings-on in my slightly agitated brain are represented by a baffling array of graphs on a screen in front of me. When I close my eyes and relax, the messy spikes and troughs become neat little waves.
Kế tiếp, scientists here at Newcastle University’s Institute of Neuroscience induce small electric currents in different parts of my head, using a technique called transcranial magnetic stimulation (TMS). If they fire the device a few millimetres to the left of my brain’s motor cortex, I feel nothing. Hit my “sweet spot”, tuy nhiên, and my arm moves of its own accord.
I’m here for a demonstration of the tools underpinning what many call “mind control” technology. Neuroscientists believe it will soon be possible for humans to control robotic avatars using the power of thought alone, or even to send thoughts or intentions from one person’s mind directly into another – a terrifying prospect for fans of cult sci-fi films such as Scanners, where society is controlled by an elite force with mind control and telepathic powers.
Some even think that people will one day connect their brains together, via the internet, to form an enormous collective super-brain.
Here in Newcastle, researchers hope such technology can be used to restore movement to people affected by paralysis or disability. In another demonstration, electrodes detect the storm of electrical activity coming from my brain down to the nerves and muscles of my arm as I move my fingers. I hear the crackle of individual motor units in my hand muscles firing, amplified through hissing speakers.
The team here are using such signals to help people control robotic limbs, or reroute nerve impulses back into the body to bypass damaged nerves. Such devices are known as brain-computer interfaces, or BCIs, and have developed rapidly over the last decade.
Internationally, neuroscientists have gone a step further, sending information from one brain into the another to create a brain-to-brain interface, or BBI. Researchers have even made one person move when another person wants them to, all by connecting their brains.
“Mind control” is suddenly not just plausible, but actually rather easy. You can buy a “DIY human-human interface” online for just over £165, part of a project aiming to make neuroscience more accessible to young people. In one video by neuroscientist Greg Gage, two on-stage volunteers are connected to the device – little more than a few wires, some flashing circuitry and a laptop. When one subject curls their arm, the other is powerless to stop their arm curling too.
“When you lose your free will and someone else becomes your agent, it does feel a bit strange,” Gage says to his young volunteers.
At the cutting edge of this technology, things get a little weirder. Ở 2013 researchers from Harvard Medical School announced they had made a device that allowed a human volunteer to move a rat’s tail via thought alone. That same year, neuroscientists from the University of Washington sent brain signals via the internet from one individual wearing an electroencephalography (EEG) headset to another with a TMS device, remotely controlling the recipient’s hand movements. One person, watching a computer game, imagined moving their hand to shoot down an enemy missile. His thoughts stimulated another person’s finger to hit the trigger at the appropriate time.
Then there’s the paralysed teenager who kicked the first ball of last year’s Fifa World Cup opening ceremony, wearing an exoskeleton controlled by his mind. And scientists at the Starlab facility in Barcelona, Ai claim to have demonstrated “conscious transmission of information” – sending the word “hola” from one mind to another, without either person using their senses.
Such experiments understandably make many people feel uneasy. Rumours that the US military is funding research in this area only add to concerns about frightening potential uses. Could people be forced to move or act against their will, or have their innermost thoughts and feelings extracted from their head?
Câu trả lời, at the moment, is almost certainly no. Even the most seemingly profound experiments can be a little underwhelming when looked at in detail. The Barcelona experiment, cho ví dụ, might sound as if one person thought “hola” and the recipient then heard the word as an inner voice in their head. The reality is very different: the “sender” spelled out the word in binary code by imagining moving their hands or feet – one movement meant “0”, the other meant “1”. The “receiver” then received two types of brain stimulation: một, which caused them to perceive flashes of light, represented the 1s, another pulse with no effect represented the 0s. Vì vậy, thực sự, one person spelled out a word by thinking about moving, and one person got a kind of futuristic Morse code blasted into their head. Impressive, but hardly The Matrix.
Vấn đề là, brain-to-brain technology in humans is currently restricted to non-invasive technologies, such as the slimy EEG device that is draped over my head in Newcastle. From outside the skull, such devices can only detect flurries of activity in the outer parts of the brain, or large spikes of activity deep in the brain.
“Reading brain activity with EEG is like trying to follow a football match while stood outside the stadium,” says Dr Andrew Jackson, senior research fellow at the Newcastle institute. “You can tell when someone’s scored a goal. But that’s about it.”
Activity associated with movement is one of the easiest types of brain activity to detect and reproduce. Capturing thoughts and feelings, which involve highly specific, synchronised activity, is something very different.
Sending sensations into the receiver’s brain is even less precise. Transcranial magnetic stimulation, the device used to make my arm twitch, can induce electric currents in extremely precise areas of the brain, activating neurons only in those areas. But again, creating complex sensations such as words and thoughts is far beyond the current scope of these devices.
Jackson says: “On the whole the technology [for sending signals] is less precise than the technology we have for recording – it is hard to control where you are stimulating. And we don’t really know much about the language of brain function – we don’t know what sensation will be created by stimulating different areas.”
Giulio Ruffini, who helped to devise the “hola” experiment, says the transmission of real thoughts or messages, rather than a sequence of 0s and 1s, is probably only likely with invasive technology – the implantation of devices directly into the brain.
“It is a far more interesting goal – the brain perceives something and you stimulate that exact experience in someone else. It has been demonstrated with invasive technologies in animals, and I believe it will be done in humans soon too.”
Such implants contain hundreds of minute needle-like electrodes, placed in precise locations in the brain to monitor or stimulate individual neurons. Researchers this year connected the brains of three monkeys using invasive technology, and found the animals quickly learned to synchronise brain activity to collaborate in tasks. In a similar experiment, four rats connected with intra-cortical devices were able to perform tasks to a higher level than single animals.
Ruffini is excited about what implants could achieve in humans. “It is so much more powerful. Already you can connect humans to an interface that controls a robot which you use to grab things. If we establish links between brains that are powerful enough, could those people actually be thought of as one and the same person? Could we even communicate with other species?"
Miguel Nicolelis, a pioneer in the field, says that if invasive technology was deemed safe and ethically permissible, “doing something like controlling a car with your thoughts would be fairly trivial”. In his book Beyond Boundaries, Nicolelis envisages a future where people “download their ancestral memory bank” or “experience the sensations of touching the surface of another planet without leaving your living room”. On the phone, tuy nhiên, he is more pragmatic. “Higher order brain functions are not available to be transmitted. If it cannot be reduced to a channel, it cannot be transmitted.”
Like Nicolelis, many working in this field like to entertain all hypothetical possibilities, despite the technology’s limitations and the complexity of the brain. Tellingly, when the UK’s scientific ethics committee looked into emerging “neurotechnologies”, such as BCIs and BBIs, they decided the discrepancy between what might be done and what is actually possible was so large that there is no need for any regulatory action for now.
Commercial attempts to create mind-reading EEG gadgets have largely been gimmicks, and when I try the £165 DIY human-human interface from the videos, I seem to just give my friends electric shocks. It all adds up to a confusing mixture of genuinely brilliant science and speculative hype.
“With some experiments I’ve seen I’m not quite sure what the point is, other than to be the first person to do it,” admits Jackson.
Dù sao, invasive devices are likely to be coming to a hospital near you, and soon. “Invasive technologies are actually more desirable for a patient who is missing a limb or is paralysed,” says Jackson. “They might not want to have to wear something on their head, they might want something permanent and incorporated into their body.” As I remove this summer’s least sought-after headwear from my poor head, I see his point. The challenge now is creating safe implants that can function beneath the skin for decades.
Others, including Ruffini, remain convinced that humans will be able to link brains more meaningfully, perhaps wirelessly, within this century.
“Humans need to communicate. We have always tried to widen the bandwidth with which we can do it – with language or letter, phone or internet. It may take 50 hoặc 100 years before we are communicating thoughts, but I think it is inevitable.”
Non-invasive brain-to-brain interfaces
■ Activity in the brain is detected by a device held on the scalp, such as electroencephalography (EEG). This gives an indication of patterns of neural activity, mainly in areas of the outer brain.
■ The data is amplified, processed, and analysed by a computer, and converted to a signal that can be transmitted into another brain.
■ Transcranial magnetic stimulation (TMS) uses a magnetic field to induce electric current in areas of the brain, stimulating neurons to “fire”. The sensations that can be created by sending impulses into the brain in this way are extremely limited, eg muscle movements or the perception of flashes of light.
Invasive brain-to-brain interfaces
■ A special chip containing tiny, needle-like electrodes is inserted into the brain and fixed to the skull. Electrodes can be placed with enough precision to measure the activity of individual neurons.
■ Activity is detected, processed and analysed by a computer.
■ Electrodes can be placed to stimulate precise areas of the brain. Though more precise than TMS, stimulating complex effects like thoughts or controlled movements is still not yet possible.
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