There may be a scientific explanation for the vivid near-death experiences, such as seeing a shining light, that some people report after surviving a heart attack, US scientists said Monday.
Apparently, the brain keeps on working for up to 30 seconds after blood flow stops, according to a study published in the Proceedings of the National Academy of Sciences.
University of Michigan scientists did their research on nine lab rats that were anesthetized and then subjected to induced cardiac arrest as part of the experiment.
In the first 30 seconds after their hearts were stopped, they all showed a surge of brain activity, observed in electroencephalograms (EEGs) that indicated highly aroused mental states.
"We were surprised by the high levels of activity," said senior author George Mashour, professor of anesthesiology and neurosurgery at the University of Michigan.
"In fact, at near-death, many known electrical signatures of consciousness exceeded levels found in the waking state, suggesting that the brain is capable of well-organized electrical activity during the early stage of clinical death."