Can You Create Out of Body Experiences?
I once woke up floating in the corner of another room of the
house--by the cieling. After looking around a bit I was suddenly
back in bed opening my eyes. I don't consider it to be anything
more than a mental phenomenon, but what's really happening when
people have out-of-body experiences? There have been two studies
published in recent years that shed some light on possible explanations.
They are "The Experimental Induction of Out-of-Body Experiences"
by H. Henrik Ehrsson and "Video Ergo Sum: Manipulating Bodily
Self-Consciousness" by Bigna Lenggenhager et al. Both were
published in Science, in August, 2007.
To better understand why people sometimes have the illusion
that they are floating above their bodies or otherwise separated
from them, these neuroscientists decided to reproduce out-of-body
experiences in a laboratory setting. They did not want to do
this by inducing strokes, epileptic fits, migraines or other
common precursors to the experiences, nor by having subjects
take drugs. Instead, they played with subjects normal perceptions
using cameras and video goggles.
Henrik Ehrsson of the Karolinska Institute in Stockholm, Sweden,
had subjects sit and use special goggles to look at a stereocopic
view of their own backs, the images coming from cameras set up
behind them. He touched the subjects chests with a rod while
stabbing at a point below and in front of the two cameras behind
them, at what would corresponded to the "virtual chest"
of each. Subjects reported that as a result of this, they felt
like they were sitting two meters behind where they actually
were.
Bigna Lenggenhager and her colleagues at the École
Polytechnique Fédérale in Lausanne, Switzerland,
did experiments that were similar. Cameras were placed a couple
meters behind each participant, who were wearing 3-D video goggles
to see the images from the cameras. Experimenters stroked their
backs with a pen so the subjects could see and feel it at the
same time. They then had the subjects move, and when told to
return to their previous position, they erred in the direction
of their "virtual" bodies by an average of ten inches.
Then the cameras were aimed at the back of a mannequin. Participants
said they felt as though the body of the mannequin was their
own body.
Both studies show how easy it is to fool the brain. Further
research may help to clarify how information from both the eyes
and the skin are used to determine one's location in space. Apparently
this information can be mis-processed by the brain when we are
ill or on drugs, leading to what seem to be out-of-body experiences.
Of course, since people are not usually wearing video goggles
during these times, the experiences also suggest the power of
our imaginations to create a scene as it would appear if we were
actually in another location.
The most immediate application of the research is not likely
to be in preventing or explaining out-of-body experiences, though.
Ehrsson and others suggest that it will be used to make better
video games. With these experiments they are learning how to
make virtual reality feel more real.
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