He explains that among those who clamed near-death experiences, 60% reported having had at least one incident where they felt sleep and wakefulness blurred together. When compared to 24% of people who had no near-death experience. These blurred periods can include sleep paralysis. Others report visual or auditory hallucinations. Such incidents can occur when some aspects of ones dream, or rapid eye movement (REM) state, during sleep intrudes into wakefulness. In REM sleep, muscles can lose their tone or tension, inducing a feeling of paralysis. The visual activity during this state may also explain the feeling of being surrounded by light.
He states that REM sleep occurs in the brainstem, which is the lower part of the brain that attaches to the spinal cord and controls most basic life functions. He hopes to further investigate near death experiences on people who have had out-of-body experiences independent of
any trauma.
Nelson doesn't rule out the possibility that other psychological or spiritual factors may also play a role. Saying that he is only interested in how this experience is generated, and not the factors contributing to them. Saying that the ultimate meanings of these experiences are questions he would leave for others to answer.
The study appears in the journal Neurology.