The brain remains conscious after the heart stops beating, according to University of Michigan researchers. It may even function higher in the moments immediately following cardiac arrest than it does when the body is in a normal state.
The finding supports the shared
experience of nearly 20 percent of people who have survived cardiac
arrest. These survivors report having internal visions and heightened
perception, known as near-death experiences, but the scientific reality
of the experience has long been debated.
In a study published Monday in the Proceedings of the National Academy of Science,
the team explains that in a study of nine rats, they observed continued
brain activity even after the heart stopped beating and blood flow
ceased. Compared to anesthesized and walking states, brain activity and
coherence actually increased immediately following cardiac arrest. While
the sample size is small, the results were observed in all nine of the
"This study, performed in animals, is the first
dealing with what happens to the neurophysiological state of the dying
brain," lead study author Jimo Borjigin, Ph.D., associate professor of
molecular and integrative physiology and associate professor of
neurology at the University of Michigan Medical School, said in a
"It will form the foundation for future human studies
investigating mental experiences occurring in the dying brain, including
seeing light during cardiac arrest," she added.