An out-of-body experience (OBE or sometimes OOBE) is a phenomenon in which a person perceives the world from a location outside their physical body. An OBE is a form of autoscopy (literally “seeing self”), although this term is more commonly used to refer to the pathological condition of seeing a second self, or doppelgänger.
The term out-of-body experience was introduced in 1943 by G. N. M. Tyrrell in his book Apparitions, and was adopted by researchers such as Celia Green, and Robert Monroe, as an alternative to belief-centric labels such as “astral projection” or “spirit walking”. OBEs can be induced by traumatic brain injuries, sensory deprivation, near-death experiences, dissociative and psychedelic drugs, dehydration, sleep disorders, dreaming, and electrical stimulation of the brain, among other causes. It can also be deliberately induced by some. One in ten people has an OBE once, or more commonly, several times in their life.
Psychologists and neuroscientists regard OBEs as dissociative experiences arising from different psychological and neurological factors.