Inverted binocular phenomenon

Disowning Pain Phenomenon (or "Inverted binocular phenomena") is the subject of a 2008 study[1] which suggested that distorting the body image can change the way people sense how it feels. For example, when a person sees an organ through inverted binoculars, it looks smaller than it really is, which may reduce the pain connected to that organ.

Ten patients with persistent discomfort in their right arms that was exacerbated by movement were instructed to move their arms while their visual impressions of those arms were adjusted. They first used binoculars to magnify how their bodies appeared, then switched to inverted binoculars to lessen the size of the image. They were also asked to rate the level of pain they felt while viewing the image. The more limbs that developed, the greater pain was felt. Binocular magnifying and minimizing can even modify the extent of edema.[2]