From the supernatural fears of the Middle Ages to modern day reality shows, all kinds of people throughout history have reported the experience of “feeling of a presence” (termed FoP by science) in what turned out to be an empty room. These feelings have usually been attributed to ghosts or spirits, and horror movies have used our collective FoP experiences to consistently freak us out. Now, scientists may have discovered the neurological root of this phenomena, using a simple study aided by a robot.
Not only are these results fascinating in explaining how healthy people can sometimes feel the otherworldly presence of, well, themselves, they could also help to find new treatments for people suffering from diseases like schizophrenia, which often provokes these symptoms in sufferers.
“Instead of creating this conflict, we want to use this robotic simulation to remove this conflict to help schizophrenic patients to restore balance,” Roginini said. “We could make them better at distinguishing themselves from someone else.”
Leading up to the experiment, Swiss neurologists studied patients with neurological problems from epilepsy, tumors, strokes, and other diseases who also reported frequent FoP. They determined that FoP probably originates in parts of the brain that deal with spatial positioning and understanding movement, the temporoparietal, insular, and frontoparietal cortex, to be exact. The researchers also found similarities in the way these patients experienced FoP, with the perceived presence of a ghost mirroring patient movements. These results lead neurologists to believe that, due to neurological confusion about the origins of bodily movement, the “ghosts people feel are actually themselves,” as Popular Science puts it.
Here’s where the robot comes in: to test this thesis, the scientists developed a very simple experiment using completely healthy subjects. Wearing a blindfold, subjects pressed a lever in front of them, which would trigger the robot to poke them from behind. This gave participants an eerie feeling of poking themselves in the back, sort of like that trick where you rub your opposite fingers and feel as if your hand is someone else’s. After establishing this sensation, the second stage of the experiment had the same participants push a lever which waited about half a second to poke them in the back. This delay caused intense FoP in the subjects, some of whom even felt they were “drift[ing] backwards toward the presence.” A few of the participants were so freaked out they couldn’t even finish the study.
“The feeling of a presence is the misattribution of signals in the brain,” Dr. Giulio Rognini, of École Polytechnique Fédérale de Lausann told Popular Science. “Their own signals are coming from the body, but they’re not properly integrated by the brain. So instead of the movements being properly attributed to themselves, they’re misattributed to another person.” If this theory is correct, the entirety of human ghost experiences have actually been our confused brains dissociating from our own body. How’s that for existential terror?