It's an otherworldly experience usually reserved for those with paranormal abilities, substance abuse problems or returning roles on "Star Trek." But now European scientists say they have induced out-of-body experiences in healthy people in a laboratory setting.
In two separate studies published simultaneously in the American journal Science this week, neuroscientists working in London and Geneva report making volunteers feel like they have left their bodies using virtual reality goggles, cameras and a plastic rod.
"I wanted to understand how we recognize our own body and how we know where in space our body is located," said Henrik Ehrsson, an assistant professor of neurology at the Karolinska Institute in Stockholm and a researcher at University College London. Ehrsson designed one of the studies.
The central question Ehrsson wanted answered was: Why do we feel ourselves located inside the physical body?
An Illusion of Body
Participants in Ehrsson's study wore goggles connected to two cameras mounted to a wall about 6½ feet behind their backs. With the cameras working like "a robot's eyes," Ehrsson said, researchers pointed a plastic stick to a point just below the cameras' field of vision. At the same time, test subjects felt another rod touch their actual chests.
Together, these elements gave volunteers the illusion they had left their bodies and were watching themselves from behind.
"They started to giggle," Ehrsson told ABC News of his volunteers' reactions. "Like, 'Wow, this is cool,' or 'Weird!' It's obvious they were experiencing something quite out of the ordinary."
"They know it's a visual trick," Ehrsson said, "but they can't think it away. It's not like they're imagining something. It's a perceptual illusion."
Ehrsson said a person's eyes, muscles and skin all work together to create a sense of self in space. When the information coming in from those senses conflicts, the brain no longer knows where it is.
"My idea is that the brain combines all sensory information to make up a model of the world and your body in that world," Ehrsson told ABC News. "If there's a breakdown in that integration, you might experience that you are in the wrong place."
The second team of researchers, led by Olaf Blanke of the University Hospital in Geneva, used a similar setup and reached the same conclusion.
Other neuroscientists expressed excitement at the studies' results.
"When you hear 'out-of-body experience' you might think of a seance or something supernatural," said Hal Blumenfeld, associate professor of neurology and neurobiology at the Yale School of Medicine. "To be able to have a normal person experience that in a controlled way is very powerful."
The Out-of-Body Market
As many as one in 10 people report having had a spontaneous out-of-body experience at some point in their lives, according to the studies' authors. Most of those occurred when the person's brain function was somehow impaired, either through injury or drug use.
Some people also claim to have left their bodies after a sudden and traumatic incident, like a car crash.
But if that sounds unpleasant, there are some who will do anything to escape their physical shells — if only temporarily.
A quick search with online retailer Amazon.com brings up hundreds of books, CDs and DVDs — ranging from how-to guides to philosophical treatises — on out-of-body traveling or "astral projection" for connoisseurs. Web sites for out-of-body enthusiasts list hundreds of testimonies from those claiming to have traveled outside their skin and willing to pass on their knowledge.
William Buhlman, author of the best-selling guide "Adventures Beyond the Body: How to Experience Out-of-Body Travel," teaches seminars on how to travel beyond oneself in locations all over the world. He says out-of-body travel helps people understand some of life's biggest mysteries.
"It's the great question of our time," Buhlman told ABC News from his home in Shanghai, China. "What happens after death?"
Buhlman, 57, says he has taken "hundreds" of journeys beyond his physical self. He teaches 40 different methods, including hypnosis and visualization, to achieve out-of-body states.
"Once you experience yourself separated from your body," Buhlman said, "no matter what anybody says, you know that you will continue beyond the body."
Karolinska's Ehrsson also expressed excitement at the no-medical possibilities of having people leave their bodies at will.
"This is essentially a means of projecting yourself, a form of teleportation," he said. "Just imagine the implications. The experience of playing video games could reach a whole new level."
Other practical applications might include doctors performing surgery from remote locations, Ehrsson said.
As to whether the studies published this week explain "spontaneous out-of-body experiences," as the nonlaboratory variety are called by both medical experts and lay enthusiasts, the studies' authors are careful not to draw any conclusions.
"We don't know if it's the same mechanism involved," Ehrsson told ABC News, adding that the absence of cameras or other equipment distinguishes spontaneous OBEs from those triggered in his study.
"But," he said of people who report having traveled beyond their physical selves and then return to tell the tale, "I think we have to take them seriously."
"Now we have a biological framework," Ehrsson said, "and we can start to talk about these things in a scientific context."