Historically OBEs were poorly studied because of their purely psychological nature; but recent technological developments have allowed neurologists to examine our states of mind much more closely, although neurological and physiological causes of OBEs have been suggested for a long time9. Dr Olaf and colleagues in Switzerland have identified the physical places in the brain where such experiences are generated2. We have found that a temporary reduction in blood or oxygen (including excess carbon dioxide in the blood) can induce out-of-body experiences "which may explain the prevalence of these sensations during accidents, emergencies, heart attacks, etc"10. Not only that, but we have been able to artificially create situations in which OBEs occur in wide-awake individuals11. Biological explanations aside, investigators have done things like placed symbols high-up in rooms (on cabinets, etc) where the patient cannot see them. Those experiencing OBEs have never seen those symbols, and sceptics who have comprehensively reviewed such experiments report that the patients only ever see what they already knew was there. In other words, it is the brain tricking the patient into thinking they are having an OBE, when in reality it is only a subjective, internal event. This, combined with our neurological understanding of OBEs is definitive proof that there is nothing supernatural occurring. As physicist Prof Stenger says, there is "no evidence for anything happening outside of the physical processes of the brain"12, a conclusion also reached by neurologist Dr Bruger11.
“One of [Dr. Olaf Blanke's] patients was a forty-three-year-old woman [and as] electrodes stimulated the area between the parietal and temporal lobes, she immediately had the sensation of leaving her body. [...] When the electrodes were turned off, however, the out-of-body sensation disappeared immediately. In fact, Dr. Blanke found that he could turn the out-of-body sensation on and off, like a light switch, by repeatedly stimulating this area of the brain.”
"The Future of the Mind" by Michio Kaku (2014)13
“Two sets of studies published independently in the same issue of the journal Science demonstrate how the illusion of a bodily self outside one's own body can be stimulated in the laboratory. The studies forge ways to better understand both out-of-body and near-death experiences. "The research provides a physical explanation for the phenomenon usually ascribed to otherworldly influences," Peter Bruger, a neurologist at University Hospital in Zurich who was not involved in the experiment, told science journalist Sandra Blakesee in her report on these experiments in The New York Times (August 24).”
Kendrick Frazier (2007)11
Olaf Blanke and his colleagues report that they are able to bring about so-called out-of-body experiences (OBE), where a person's consciousness seems to become detached from the body, by electrical stimulation of a specific region in the brain. I have discussed OBE experiments in two books and have concluded that they provide no evidence for anything happening outside of the physical processes of the brain.”
"God, the Failed Hypothesis: How Science Shows That God Does Not Exist" by Prof. Victor J. Stenger (2007)14