Asked by: Robert Lucas, West Malling
Imagine feeling as though you are floating above your body, looking down upon your physical self. Some argue that such out-of-body experiences (OBEs) prove that the conscious mind – or even the soul – can leave the body. Supporting this interpretation, people who have survived a near-death experience often recall experiencing this out-of-body sensation – as if their spiritual essence had separated from their corporeal existence.
However, the scientific explanation for OBEs is more terrestrial. Neuroscientists and psychologists believe it has to do with neural processes going awry. In those who come close to death, such as cardiac arrest survivors, it is the lack of oxygen to the brain, and the release of certain neurochemicals triggered by trauma, that interferes with the sensory functions that support our usual feelings of embodiment. People’s recollections of seeing themselves from above – such as observing surgeons working on their body – could be a form of hallucination or false memory, as they try to make sense of their experiences.
Consistent with the scientific explanation is the fact that OBEs are far more common among people with vestibular problems (the vestibular system is located in the inner ear and is crucial to our sense of balance and spatial orientation). Also, psychedelic trips, especially those associated with ketamine and DMT, can trigger OBEs, probably due to their effect on sensory processing in the brain.
What’s more, researchers have induced out-of-body states in healthy volunteers simply by confusing their sensory systems. For instance, scientists at the Karolinska Institute in Stockholm asked volunteers to wear goggles that showed the perspective of a camera placed behind them (so that they could see themselves from behind). When a researcher prodded the camera with a baton at the same time as prodding the person’s chest, the volunteer had the sensation that they were floating behind their physical body. The fact it is possible to induce an OBE argues against more mystical explanations.