Near-death experience is a profound set of sensations sometimes reported by people who come close to death and then recover. It is often abbreviated NDE. People who have undergone near-death experiences often describe similar sensations. These include feelings of peace and a sense of being outside the physical body. Many people also report a sense of moving through a dark tunnel and encountering a bright light. Some people tell of meeting other spiritual beings. Some people who report near-death experiences have been pronounced dead by physicians and only later revived. Typically, the person experiences a return to the physical body when revived.
Many people who have a near-death experience find that it dramatically and permanently alters their attitudes, beliefs, and values. Common changes include increased spirituality and compassion and concern for others. People also report a greater appreciation of life, a greater sense of purpose, and a belief in life after death.
People of all ages, religions, and ethnic groups undergo near-death experiences. Scientific studies show that such experiences happen to people who are psychologically healthy beforehand. Scientists have proposed several theories to explain near-death experiences. Most of them involve various physiological changes in the brain or psychological processes that occur as a person nears death. However, there is little evidence to support any one theory. Scientists are interested in near-death experiences in part because they may provide important insights about the relationship between the brain and the mind.