Virtual Reality

Scientists claim that 'self' can relocate to other bodies, or be made to include a third arm

Scientists claim that 'self' c...
Neoroscientists claim that the transference of one's self to another body (as depicted here in the film 'Metropolis') is possible, on a psychological level
Neoroscientists claim that the transference of one's self to another body (as depicted here in the film 'Metropolis') is possible, on a psychological level
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Neoroscientists claim that the transference of one's self to another body (as depicted here in the film 'Metropolis') is possible, on a psychological level
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Neoroscientists claim that the transference of one's self to another body (as depicted here in the film 'Metropolis') is possible, on a psychological level
The 'third arm' experiment being performed at Karolinska (Photo: Henrik Ehrsson)
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The 'third arm' experiment being performed at Karolinska (Photo: Henrik Ehrsson)

For millennia, philosophers have debated whether or not the self exists solely in the mind, the body, or both. Well, it's unclear whether this will help clear things up or just muddy the waters further, but Swedish neuroscientists are now claiming that the human brain can add outside objects such as a third arm to one's physical sense of self, and that people can even mentally project their "self" out of their own body and into someone else's. If these findings hold up, the implications for virtual reality, robotics and prostheses could be substantial.

Experiments were performed at Stockholm's Karolinska Institutet medical university, in which a highly-realistic prosthetic right arm was placed on a table beside human subjects' own arms, so they could see all three. Scientists then simultaneously touched both the prosthetic arm and the subjects' own right arms with a small brush, at the same location on both arms.

"What happens then is that a conflict arises in the brain concerning which of the right hands belongs to the participant's body," said Arvid Guterstam, one of the scientists conducting the research. "What one could expect is that only one of the hands is experienced as one's own, presumably the real arm. But what we found, surprisingly, is that the brain solves this conflict by accepting both right hands as part of the body image, and the subjects experience having an extra third arm."

The 'third arm' experiment being performed at Karolinska (Photo: Henrik Ehrsson)
The 'third arm' experiment being performed at Karolinska (Photo: Henrik Ehrsson)

When scientists threatened either the prosthetic arm or the real arm with a knife, the subjects' measured stress response was the same.

It is hoped that the scientists' findings could eventually be applied to people such as partially-paralyzed stroke victims, so that they could incorporate a functioning prosthetic arm into their body image while still also retaining their existing paralyzed arm within that image. It has even been suggested that resulting technology could have applications for people in demanding work situations such as paramedics or firemen, who could always use an extra arm.

Transferring the self

A related study at Karolinska is said to have resulted in people perceiving that their physical selves were located not in their own bodies, but in those of other test subjects. We're currently waiting to hear back from the university, as to how this was achieved or verified."By clarifying how the normal brain produces a sense of ownership of the body, we can learn to project ownership onto artificial bodies and simulated virtual ones, and even make two people have the experience of swapping bodies with one another," stated study leader Henrik Ehrsson.

So far, he has reportedly been able to "transfer" subjects' selves into bodies of a different sex, age, or size, but not into inanimate objects. In one ongoing robotics-related project, however, researchers are trying to determine if someone's perceived body can be shrunk down to the size of a Barbie doll.

22 comments
Daniel Plata Baca
Self is Soul, a transparentlike ONLY FULL body , in wich you can see your own bones.
Smokey_Bear
Doc Oc already proved this 2 spiderman movies ago...
Kiel Stuart (@kielrhys)
philosophers. as long as there are absolutists there will be philosophers. for everone in between, the people who aren\'t stuck in the renaissance, they\'re all just annoying. honestly i think philosophers are for the most part scared people who aren\'t willing to take a chance, and don\'t like the idea of being left behind so they try and hold everyone back while hiding behind a mask of wisdom. if it were up to the absolutists we had the answer to everything from the beginning. if it were up to the philosophers we\'ll never have any answers. between the two of them we have managed to survive this far, but in 2011 they\'re just slowing us down. going all neo-mystic and pondering the idea of self is like pondering the existance of a chair, honestly it\'s rediculous. this self might just be a collection of matter in an elaborate form, but it still freakin exists. honestly these people are lost in their own head. words grounded on nothing are just pointless maths. they mean nothing
Jacob William
Great article Ben! I\'d be very interested to hear more on the Karolinska study.
@gimeney cricket You have a very shallow understanding of what you are talking about. Further, your position is actually absolute in its conclusions, which is hypocritical if not somewhat, you know, stupid, considering what you are trying to argue. I suspect your post is a form of procrastination.
Ben Crumpacker
OF COURSE they would tell you this just before they KILL you!
Scion
This isn\'t exactly new. I remember this type of study from when I did psychology at uni nearly 20 years ago. Also, here is an e-how that demonstrates the same or at least similar principle http://www.wikihow.com/Feel-Like-You-Have-Two-Noses
And any guy who has watched Funniest Home Videos will know it is possible to feel another man\'s pain...
Facebook User
Im writing this in Sydney but Im really in Honolulu.
Facebook User
Sounds more like a trick of the mind and your own perceptions rather than any real transference of consciousness or anything beyond a neat trick... kinda like when you flinch or cringe when watching someone else get cut on TV or in a movie, you can almost feel the sensation of what you see on the screen... just another neat trick or psychological phenomenon...
Chris Maresca
This is nothing new, Jaron Lanier discovered this in the early 1980\'s when a VR immersion program went haywire and he wound up with a huge thumb. Through experimentation, he discovered how to manipulate new, artificial virtual limbs. Saw him talk about this at a TED talk here: http://www.youtube.com/watch?v=IwbGumZ-FYg&feature=player_embedded
Loving It All
Ir seems likely that what\'s going on here is mental confusion rather than synthesis. With extended experience, the mind will learn to distinguish ever more subtle differences between visual images and other sensory input, and then once again will draw the distinction between self and non-self/other.
This is not to deny cognitive plasticity, only to say that I don\'t think this study has that much to say about it.