The concept of death has obsessed human beings since the dawn of time.
What happens after death?
There isn't a comprehensive or clear answer.
We did think we knew how to determine death, or when a person is no longer considered alive, from a medical or biological standpoint.
But now even that is being called into question because of a new study published in the Canadian Journal of Neurological Sciences.
Did doctors just discover life continues after death?
Doctors in a Canadian intensive care unit found a person's brain continued to be active for 10 minutes after they'd been declared clinically dead.
They observed what happened after taking four critically ill patients off life support and found brain activity only persisted with one of the patients after the final heartbeat.
This patient exhibited the same kind of brain waves that are seen during deep sleep for a little over 10 minutes after they were declared clinically dead (they had no pulse and nonreactive pupils).
But, the doctors also found all four of the patients' brains behaved differently after they were declared clinically dead.
Long story short, death is incredibly mysterious, and we still know very little about what actually happens after life ends.
This study may have confused things even further.
The doctors aren't sure what to make of this.
The doctors involved in this study aren't sure how to explain what happened, but they did say they don't think it's a product of human error, and all the machines involved were working properly.
This challenges previous research that found the brain ceases all activity after one last surge, called a "wave of death," roughly a minute after death.
Still, the doctors are reluctant to make any big assumptions based on what they observed.
Mainly, it leaves us with far more questions than answers, and further research is clearly needed.