Just happened upon this article. My interest from the SI perspective is the 
quite natural and assuming use of SI only (no Imperial added).

Unfortunately, this same item broadcast or posted by the BBC would undoubtedly 
tack on the inevitable parenthetical Imperial. I just hope they get turned 
around soon enough.

Ezra

==============

First out-of-body experience induced in laboratory setting

24 August 2007

A neuroscientist working at UCL (University College London) has devised the 
first experimental method to induce an out-of-body experience in healthy 
participants. In a paper published today in Science, Dr Henrik Ehrsson, UCL 
Institute of Neurology, outlines the unique method by which the illusion is 
created and the implications of its discovery. An out-of-body experience (OBE) 
is defined as the experience in which a person who is awake sees his or her own 
body from a location outside the physical body. OBEs have been reported in 
clinical conditions where brain function is compromised, such as stroke, 
epilepsy and drug abuse. They have also been reported in association with 
traumatic experiences such as car accidents. Around one in ten people claim to 
have had an OBE at some time in their lives.

Dr Ehrsson said: “Out-of-body experiences have fascinated mankind for 
millennia. Their existence has raised fundamental questions about the 
relationship between human consciousness and the body, and has been much 
discussed in theology, philosophy and psychology. Although out-of-body 
experiences have been reported in a number of clinical conditions, the 
neuro-scientific basis of this phenomenon remains unclear.

“The invention of this illusion is important because it reveals the basic 
mechanism that produces the feeling of being inside the physical body. This 
represents a significant advance because the experience of one’s own body as 
the centre of awareness is a fundamental aspect of self-consciousness.”

Discovering this means of inducing an OBE could also have industrial 
applications, as Dr Ehrsson explains: “This is essentially a means of 
projecting yourself, a form of teleportation. If we can project people into a 
virtual character, so they feel and respond as if they were really in a virtual 
version of themselves, just imagine the implications. The experience of playing 
video games could reach a whole new level, but it could go much beyond that. 
For example, a surgeon could perform remote surgery, by controlling their 
virtual self from a different location.”

The set-up of the illusion is as follows: the study participant sits in a chair 
wearing a pair of head-mounted video displays. These have two small screens 
over each eye, which show a live film recorded by two video cameras placed 
beside each other two metres behind the participant’s head. The image from the 
left video camera is presented on the left-eye display and the image from the 
right camera on the right-eye display. The participant sees these as one 
‘stereoscopic’ (3D) image, so they see their own back displayed from the 
perspective of someone sitting behind them.

The researcher then stands just beside the participant (in their view) and uses 
two plastic rods to simultaneously touch the participant’s actual chest 
out-of-view and the chest of the illusory body, moving this second rod towards 
where the illusory chest would be located, just below the camera’s view.

The participants confirmed that they had experienced sitting behind their 
physical body and looking at it from that location. Dr Ehrsson said: “This was 
a bizarre, fascinating experience for the participants – it felt absolutely 
real for them and was not scary. Many of them giggled and said ‘Wow, this is so 
weird!’”.

To test the illusion further and provide objective evidence, Dr Ehrsson then 
performed an additional experiment to measure the participants’ physiological 
response – specifically the level of perspiration on the skin – in a scenario 
where they felt the illusory body was threatened. Their bodily response 
strongly indicated that they thought the threat was real.

The creation of this perceptual illusion stems from an idea Dr Ehrsson had as a 
medical student, when he wondered what would happen to the ‘self’ if you could 
effectively move your eyes to another part of the room, just a few metres away, 
so you could observe yourself from an outside perspective. Would the self 
‘follow’ the eyes or stay in the body?

Dr Ehrsson added: “The illusion is different from anything published 
previously. It is the first to involve a change in the perceived location of 
the self, relative to the physical body. It is also different from any virtual 
reality set-up because it examines what happens when you look at yourself, and 
there is also multisensory information that triggers the illusion. There has 
been no way of inducing an OBE in healthy people before, apart from 
unsubstantiated reports in occult literature. It’s a very exciting development, 
and has implications for a range of disciplines from neuroscience to theology.”

Reply via email to