Experiments Get Close to 'Out-of-Body' Experience

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Nelson believes that neither team fully replicated the "out-of-body" state but did create a convincing "illusion."

"I think these are very clever and interesting experiments," he added. "And I think they show the importance of the visual system in how we integrate our identity of self in space."

In other words, the two experiments create a visual illusion that is so convincing to the brain that it somehow disrupts the usually seamless integration between the eyes, touch and proprioception, Nelson said. The result -- which might also occur during sleep-wake transitions, as the brain is put under stress near death, or in certain medical conditions -- is that sensation of temporarily losing contact with the body.

None of this means that vision is the key component, Nelson said. "If we were able to manipulate another [sense] in such a comprehensive or complete fashion, maybe we'd get similar results," he added.

"There's a simple way of proving that," he said. "Close your eyes. Can you still tell where you are or where your body is? You can. You have no visual input, yet you still retain that sense of self and where you are in space."

He agreed with Blanke that your close identification with your own body was essential to the illusion, since viewing a dummy body had no effect.

"Full body consciousness seems to require not just the 'bottom up' process of correlating sensory information but also the 'top down' knowledge about human bodies," Blanke said in a statement.

The new findings have implications beyond neuroscience, he added. They might lead to better and more "real" video gaming technologies, or even surgeries where doctors conduct procedures from a distance.

Blanke's research team even included one philosopher -- because the connection between the body and consciousness runs to the heart of much of theology and philosophy.

Nelson said it's tempting -- but probably erroneous -- to infer any higher spiritual meaning from these scientific findings, however.

"Does this ultimately prove a certain duality or spiritual, Platonic kind of existence?" he said. "No, these are totally separate [investigations], and people get them muddled and confused."

More information

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