Ursi's Eso Garden

Out-of-body experience recreated

Experts have found a way to trigger an out-of-body experience in volunteers.

The experiments, described in the Science journal, offer a scientific explanation for a phenomenon experienced by one in 10 people. Two teams used virtual reality goggles to con the brain into thinking the body was located elsewhere. The visual illusion plus the feel of their real bodies being touched made volunteers sense that they had moved outside of their physical bodies.

The researchers say their findings could have practical applications, such as helping take video games to the next level of virtuality so the players feel as if they are actually inside the game. Clinically, surgeons might also be able to perform operations on patients thousands of miles away by controlling a robotic virtual self.

For some, out-of-body experiences or OBEs occurs spontaneously, while for others it is linked to dangerous circumstances, a near-death experience, a dream-like state or use of alcohol or drugs.

One theory is that it is down to how people perceive their own body - those unhappy or less in touch with their body are more likely to have an OBE.

But the two teams, from University College London, UK, and the Swiss Federal Institute of Technology in Lausanne, believe there is a neurological explanation. Their work suggests a disconnection between the brain circuits that process visual and touch sensory information may thus be responsible for some OBEs. In the Swiss experiments, the researchers asked volunteers to stand in front of a camera while wearing video-display goggles.



"We feel that our self is located where the eyes are"
UCL researcher Dr Henrik Ehrsson


Through these goggles, the volunteers could see a camera view of their own back - a three-dimensional "virtual own body" that appeared to be standing in front of them. When the researchers stroked the back of the volunteer with a pen, the volunteer could see their virtual back being stroked either simultaneously or with a time lag. The volunteers reported that the sensation seemed to be caused by the pen on their virtual back, rather than their real back, making them feel as if the virtual body was their own rather than a hologram.

Even when the camera was switched to film the back of a mannequin being stroked rather than their own back, the volunteers still reported feeling as if the virtual mannequin body was their own. And when the researchers switched off the goggles, guided the volunteers back a few paces, and then asked them to walk back to where they had been standing, the volunteers overshot the target, returning nearer to the position of their "virtual self".

Dr Henrik Ehrsson, who led the UCL research, used a similar set-up in his tests and found volunteers had a physiological response - increased skin sweating - when they felt their virtual self was being threatened - appearing to be hit with a hammer. Dr Ehrsson said: "This experiment suggests that the first-person visual perspective is critically important for the in-body experience. In other words, we feel that our self is located where the eyes are."

Dr Susan Blackmore, psychologist and visiting lecturer at the University of the West of England, said: "This has at last brought OBEs into the lab and tested one of the main theories of how they occur. "Scientists have long suspected that the clue to these extraordinary, and sometimes life-changing, experiences lies in disrupting our normal illusion of being a self behind our eyes, and replacing it with a new viewpoint from above or behind."

Source: BBC News

Elsewhere about the study:
Why being out of the body is all in the mind by Times Online.
Out-of-body experiences are 'all in the mind' by NewScientist.


Olaf Blanke, of the Federal Polytechnic of Lausanne (EPFL) in Switzerland, explains how it was done:




It's news to me. Notably, this new study is the first to demonstrate something akin to an 'out-of-body-experience'.
But it's not really the same as the classic experience where you see your body in front of you, perhaps as you float above it, something known as autoscopy or heautoscopy in the medical literature.
So in my opinion the OBE is not explained with this nice experiment.

In fact, you can do something similar at home.

Our brains are constantly updated with information about the position of our bodies. Rather than relying entirely on one form of sensory feedback,
our bodies use both visual and tactile feedback in concert to allow us to work out where, our limbs are likely to be at any one moment.

Proprioception - generated by sensory receptors located in our joints and muscles that feed back information on muscle stretch and joint position - is
another sense that is specifically concerned with body position.

The brain combines all this information to provide a unified impression of body position and shape known as the body schema. Nevertheless, by supplying
conflicting sensory feedback during movement, we can confuse our body schema and break apart the unified impression.

In Action

Find a mirror big enough so you can stand it on its edge, perpendicular to your body, with the mirrored side facing left. Put your arms at your sides
(you’ll probably need a friend to hold the mirror).
Look sideways into the mirror so you can see both your left hand and its reflection in the mirror, so that it appears at first blush to be your hidden right hand. While keeping your wrists still and looking into the mirror, waggle your fingers and move both your hands in synchrony for about 30 seconds.

After 30 seconds, keep your left hand moving but stop your right. You should sense a momentary feeling of “strangeness,” as if disconnected from your right hand. It looks as if it is moving yet feels as if it has stopped.

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One easy way of moving your hands together is to run a
curtain rail under the mirror, if you have one handy, and place
each hand on a curtain ring. Move your hands toward and away from the
mirror for 30 seconds, until your brain has confused
your right hand and your reflected left hand in the mirror - then
release the curtain ring from your right hand. You can feel
the ring has gone, but in the mirror it looks as though you’re
still holding it. To me, the disconnect felt like pins and needles,
all through my right hand.

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Alternatively, you can manipulate your body schema into incorporating a table as part of yourself. Sit at a table with a friend at your side. Put one
hand on your knee, out of sight under the table. Your friend’s job is to tap, touch, and stoke your hidden hand and—with identical movements using
her other hand—to tap the top of the table directly above. Do this for a couple of minutes. It helps if you concentrate on the table where your friend is
touching, and it’s important you don’t get hints of how your friend is touching your hidden hand. The more irregular the pattern and the better synchronized the movements on your hand and on the table, the greater the chance this will work for you. About 50% of people begin to feel as if the
tapping sensation is arising from the table, where they can see the tapping happening before their very eyes. If you’re lucky, the simultaneous touching
and visual input have led the table to be incorporated into your body image.

Source:  Mould Your Body Schema by Vaughan Bell (PDF), Institute of Psychiatry