A new method to induce phantom limbs

We present a simple method using a dark room and a camera flash to induce three novel “out of body” effects. If one is dark adapted, a brief, bright flash may bleach the photoreceptors, allowing whatever is seen during the flash to be “imprinted” on the retinas for several seconds. 1) To induce a feeling of weightlessness, seated subjects looked at their legs during the flash and, after the positive afterimage had formed, directed their eyes to the ceiling. The afterimage of their legs was then projected onto the ceiling, inducing a feeling of weightlessness. 2) To induce a feeling of “phantom” limbs, seated subjects, with feet on the ground, were instructed to look at their thighs and the ground in front of them during the flash. After the positive afterimage had formed, subjects straightened their legs. This uncoupled the visual feedback (seeing a static image of the ground in front of them) from the proprioceptive feedback (feeling their legs move in front of them). Subjects reported that their legs felt lighter than normal and like ghost or “phantom” legs. (Patients with phantom limbs experience similar discrepancies between visual feedback and where they feel their phantoms moving.) Some subjects even reported a loss of ownership of their legs, stating that they felt like they no longer had legs! 3) If the converse is tried (subjects extend their legs, look at their extended legs during the flash and, after the positive afterimage has formed, bend their legs, a feeling of paralysis was reported. The visual image of “legs straight” remained unchanged while the proprioceptive movement suggested otherwise. These effects may have relevance to chronic pain and fibromyalgia, as out of body experiences may allow chronic pain sufferers to feel “outside” of their pain.