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Now We Know What It Feels Like to Be Invisible

First, Arvid Guterstam made himself invisible. When he looked down at his body, there was nothing there.

He could feel he was solid; he hadn’t vanished into thin air. He even felt a paint brush tickle his transparent belly, while the brush appeared to be stroking nothing but air.

Being invisible is “great fun,” Guterstam reports, “but it’s an eerie sensation. It’s hard to describe.”

Then he took off his virtual reality headset and was back in the laboratory, fully visible. Guterstam is a medical doctor and PhD student, and he had just pulled off the first fully convincing illusion of complete invisibility. He went on to test 125 other people, and reports Thursday in Scientific Reports that seven out of ten also felt the illusion, and it was realistic enough to make them feel and respond physically as if a group of people could not see them.

One day, just maybe, cloaking devices might make human invisibility possible. Guterstam wants to know what that will feel like—and what these people might do. How about their morals? If you take away the chance of being caught, will people, as we might suspect, lose their sense of right and wrong?

But before he can test the moral fortitude of the newly transparent, Guterstam has to get people to feel completely invisible. He and his colleagues in Henrik Ehrsson’s laboratory at Sweden’s Karolinska Institute have succeeded at many other body-morphing illusions, including making my Phenomena colleague Ed Yong feel in turn that he had left his body, shrunk to the size of a doll, and grown a third arm.

They already convinced people they had an invisible hand. But what about the whole body? “This is definitely pushing the boundaries of how bizarre an illusion of this kind can get,” Guterstam says.

Gustav Mårtensson
A simple trick creates the illusion of an invisible hand. Gustav Mårtensson
A simple trick creates the illusion of an invisible hand.

This time, they had people put on a virtual-reality headset that showed the view from a second headset, mounted at head height on nothingness. If you were in this getup, a scientist would touch you with a paint brush while simultaneously touching the nothingness in the same place, as though a body were there. So as you felt the brush, your eyes would be telling you that the brush was touching your nothingness body.

When a scientist swiped a knife toward the invisible belly, people’s heart rates went up and they broke out in a sweat, the classic stress response. When put in front of an audience of serious-looking people staring them down, “visible” people also got stressed. But the “invisible” people—not so much. They felt so completely invisible that their bodies responded as though they really were invisible. Since the audience couldn’t see them, there was no reason to feel uncomfortable.

The illusion works because, as the team has learned from these tricks, it’s shockingly easy to create an out-of-body experience. Our sense that we reside within our bodies—what we can think of as our sense of self—is not fixed. Instead of being firmly locked in our body, our sense of self can float free, as if on a tether.

Our brains, it appears, create this body sense moment by moment, continuously monitoring our senses and putting the “me” where those senses say it should be. Move the senses, and you move the me. All it takes is creating a mismatch between where I see I’m being touched and where I feel it.

This is all very interesting, but what do we do with it? Well, Ehrsson’s group is also working on better prosthetic devices for amputees, that would harness the sense of self to make the prosthetic feel like a true body part. One day, we might even control robots with our movements and actually feel that we’ve jumped into the robotic body.

And then there’s the dream of actual invisibility, with all its moral dilemmas. For now, we don’t need to fret too much: The closest we’ve gotten is disappearing a cat and a goldfish, and only behind a fixed cloaking device and from the right angles.

All this talk of invisibility leads, inevitably, to The Question. A question whose answer, many believe, says something deep about each of us. If you could be the only person on Earth with a superpower, and you could choose between flight and invisibility, which would you choose?

Flight, many feel, is the noble choice. Invisibility is for thieves and perverts. Yet when we’re honest with ourselves, that’s exactly what many of us are, so invisibility maintains its secret allure.

And Arvid Guterstam? “I would probably say flying,” he says.

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Is crime a virus or a beast? How metaphors shape our thoughts and decisions

In 1990, in a depressed area of Buffalo, New York, eleven schoolgirls were raped. According to George Kelling, a criminal justice scholar, eight of these incidents could have been prevented. After the third case, police knew that a serial rapist was on the loose but, even though they had a description and modus operandi, they issued no warning to local parents. They saw their job as catching the criminal rather than preventing more girls from being raped.

Kelling argued that the cops hadn’t wilfully neglected their duties. Their actions were swayed by their views of police-work, which were in turn affected by metaphors. They saw themselves as crime-fighters who trod the “thin blue line” protecting innocent civilians from criminal marauders. With this role entrenched in their minds, they saw their job as catching the rapist, even at the expense of preventing further crimes. As Kelling said, the eight Buffalo schoolgirls “were victims, though no one realized it at the time, not only of a rapist, but of a metaphor.”

As with all complex issues, crime is suffused with metaphors. One common frame portrays crime as a disease, one that plagues cities, infects communities, and spreads in epidemics or waves. Another depicts crime as a predator – criminals prey upon their victims, and they need to be hunted or caught. These aren’t just rhetorical flourishes; they’re mind-changing tools with very real consequences.

In a series of five experiments, Paul Thibodeau and Lera Boroditsky from Stanford University have shown how influential metaphors can be. They can change the way we try to solve big problems like crime. They can shift the sources that we turn to for information. They can polarise our opinions to a far greater extent than, say, our political leanings. And most of all, they do it under our noses. Writers know how powerful metaphors can be, but it seems that most of us fail to realise their influence in our everyday lives.


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Heavy, rough and hard – how the things we touch affect our judgments and decisions


When you pick up an object, you might think that you are manipulating it, but in a sense, it is also manipulating you. Through a series of six psychological experiments, Joshua Ackerman from the Massachusetts Institute of Technology has shown that the properties that we feel through touch – texture, hardness, weight – can all influence the way we think.

Weight is linked to importance, so that people carrying heavy objects deem interview candidates as more serious and social problems as more pressing. Texture is linked to difficulty and harshness. Touching rough sandpaper makes social interactions seem more adversarial, while smooth wood makes them seem friendlier. Finally, hardness is associated with rigidity and stability. When sitting on a hard chair, negotiators take tougher stances but if they sit on a soft one instead, they become more flexible.

These influences are not trivial – they can sway how people react in important ways, including how much money they part with, how cooperative they are with strangers, or how they judge an interview candidate.