New research demonstrates that triggering an out-of-body experience (OBE) could be as simple as getting a person to watch a video of themselves with their heartbeat projected onto it. According to the study, it's easy to trick the mind into thinking it belongs to an external body and manipulate a person's self-consciousness by externalizing the body's internal rhythms. The findings could lead to new treatments for people with perceptual disorders such as anorexia and could also help dieters too.
In a typical out-of-body experience a person either experiences a feeling of floating outside of their body or of viewing it from outside of themselves. Most of us don't experience OBE's because our brains are constantly filtering information from all our senses to help us identify what we are and what we aren't.
For instance we know that our reflection isn't actually part of us. However the processes that give us the feeling of being in our bodies can be disrupted either naturally (seizures) or artificially (feeding the brain conflicting sensory inputs). For example, in the well known "rubber hand" illusion, a person begins to identify more with a rubber hand when someone strokes it in front of them, while stroking their real hand out of sight.
It's possible to expand this feeling to include the whole body as demonstrated in experiments that get a person to identify more with a virtual double than their own body by using virtual reality goggles. However, all of these experiments rely on manipulating external senses such as vision and touch.
Not much is known about how information from our internal organs contributes to bodily self-consciousness and whether they can be manipulated to induce an OBE. That's the question Dr Jane Aspell, Senior Lecturer in Psychology, Anglia Ruskin University, UK and Lukas Heydrich, Phd Student, Laboratory of Cognitive Neuroscience, Ecole Polytechnique Fédérale de Lausanne (EPFL), Switzerland, set out to answer.
"If you think about your body, you have several sources of information about it: you can see your hands and legs, you can feel the seat you're sitting on via vision, you know you are standing upright thanks to your sense of balance etc," Aspell tells Gizmag. "There is also a vast number of signals being sent to your brain from inside of your body every second that you are alive: about your heartbeat, your blood pressure, how full your stomach is, what electrolytes are in your blood, how fast you are breathing.
"There is a huge amount of diverse information being sent to your brain about your body and yet what you perceive is not these medley of signals but just you – a single body, a single self. These pieces of information about the external and internal states of your body must be integrated or merged to generate this unity. This is what we are now beginning to study for the first time."
Aspell and Heydrich decided to find out whether a person's bodily self-consciousness could be influenced by visually representing one of its vital inner rhythms – the pulsing heartbeat. They attached 17 participants to electrocardiogram sensors and had them view videos of their bodies through virtual reality goggles so that their body appeared to be two meters (6.5 ft) in front of them.
Participants saw their own heartbeats visually imposed on their virtual doubles in the form of a flashing outline around the body that pulsed in sync. After a couple of minutes, many of the participants reported sensations of being in an entirely different part of the room rather than their physical body and feeling that their "selves" were closer to their virtual doubles.
According to the team, this is the first study that clearly shows how visual signals containing information about the body's internal organs (in this case, the heartbeat) can change their perception of themselves. "It confirms that the brain is able to integrate visual information with cardiac information," says Aspell. "It seems that the brain is very sensitive to patterns in the world which may relate to self – when the flashing was synchronous with the heartbeat this caused changes to subjects' self-perception."
The research could help people with distorted views of themselves to connect with their actual physical appearance. "Patients with anorexia seem to identify with a body which is larger than their physical body," Aspell tells us. "We could use this manipulation to help patients with anorexia to identify with their actual physical self."
Aspell is currently studying "yo-yo" dieters and says she plans to continue investigating "how the internal body shapes who we are." The Swiss National Science Foundation and the Fondation Bertarelli supported the study which is slated for publication in the APS journal Psychological Science.
The experiment can be seen in the video below