Scientists create out-of-body illusion and ‘teleport’ participants around a room

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By: Ryan Whitwam

Neuroscientists from Sweden’s Karolinska Institutet have managed to induce an “out-of-body” experience in 15 healthy volunteers, and it was considerably easier than you might think. Study participants were essentially tricked into associating their own physical body with an image being streamed to them from a different area of the room. The perceived location of the participants could also be decoded from their brain activity, the study claims.

The experimental setup was remarkably simple. Each test subject was placed in an MRI and fitted with a head-mounted display. The video streamed to that display showed a first-person perspective of a stranger’s body across the room, as seen in the image above. This by itself wasn’t enough to produce a feeling of being out of one’s own body, but all it took to scramble the brain’s location-sensing apparatus was to touch the participant’s body at the same time the video showed the stranger’s body being touched in the same place.

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According to the researchers, it only took a few seconds for all 15 participants to feel the sensation of actually being on the other side of the room. The brain merges the sensation of touch with the visual input and can only conclude that it’s inside the stranger’s body across the room. This shows how delicate and complex the seemingly simple task of knowing where you are can be. In fact, discoveries about the role of place and grid cells in this process won the Nobel Prize for medicine last year.

The point of having study participants in the MRI machine during the experiment was to observe activity in areas of the brain that are known to shape our positional awareness. The researchers found that observing the hippocampus (an area with many “place” cells) allowed them to identify when the brain began associating physical location with the stranger’s body. This tells us place cells have more to do with perceived location than we though, and also that virtual reality is pretty serious business.