Brain Activity Has Been Recorded as Much as 10 Minutes After Death

Doctors can't explain it.

Doctors in a Canadian intensive care unit stumbled on a very strange case last year - when life support was turned off for four terminal patients, one of them showed persistent brain activity even after they were declared clinically dead.

For more than 10 minutes after doctors confirmed death through a range of observations, including the absence of a pulse and unreactive pupils, the patient appeared to experience the same kind of brain waves (delta wave bursts) we get during deep sleep.
And it's an entirely different phenomenon to the sudden 'death wave' that's been observed in rats following decapitation.

The big takeaway from studies like these isn't that we understand more about the post-death experience now than we did before, because the observations remain inconclusive and without biological explanation.

SOURCE:  https://www.sciencealert.com/brain-activity-has-been-recorded-as-much-as-10-minutes-after-death