In their last minutes of life, some people’s brains generate a surge of surprisingly organized-looking electrical activity that may reflect consciousness — although scientists aren’t entirely sure.

According to new research, published Monday (May 1) in the journal PNAS(opens in new tab), this surge can sometimes occur after a person’s breathing stops but before the brain stops functioning. The activity pattern is somewhat similar to what is seen when people are awake or in dreamlike states, leading to speculation that perhaps these electrical surges reflect the otherworldly experiences reported by people who’ve had close brushes with death: A sense of looking at the body from the outside; a tunnel and white light; or a sense of reliving important memories.

However, since all the patients in the new study ultimately died, it’s impossible to know if they had such experiences.

“If you talk about the dying process, there is very little we know,” said Jimo Borjigin(opens in new tab), a neuroscientist at the University of Michigan Medical School who led the study. It’s rare for patients to have their brains continuously monitored as they die, Borjigin told Live Science. “This is maybe the first study to really show second-by-second how the brain dies.”

more at livescience.com