A near-death experience (NDE) is a profound personal experience associated with death or impending death, which researchers describe as having similar characteristics. When positive, which the great majority are, such experiences may encompass a variety of sensations including detachment from the body, feelings of levitation, total serenity, security, warmth, joy, the experience of absolute dissolution, review of major life events, the presence of a light, and seeing dead relatives. When negative, such experiences may include sensations of anguish, distress, a void, devastation, and seeing hellish imagery.NDEs usually occur during reversible clinical death. Explanations for NDEs vary from scientific to religious. Neuroscience research hypothesizes that an NDE is a subjective phenomenon resulting from "disturbed bodily multisensory integration" that occurs during life-threatening events. Some transcendental and religious beliefs about an afterlife include descriptions similar to NDEs.In the U.S., an estimated nine million people have reported an NDE according to a 2011 study in Annals of the New York Academy of Sciences. Most of these near-death experiences resulted from serious injury affecting the body or brain.