When you’re dead, you’re dead. Once your brain stops “waving,” you’re as good as gone.
Well, maybe not. An ethically-questionable experiment has seen scientists revive the brain cells of pigs 4 hours after they died. The experiment did not produce consciousness, but the study blurs the line between what science considers “alive” and “dead.”
It also raises the question: Could a dead brain be brought back to life?
The scientists behind the experiment jump-started the blood vessels in the pigs’ brains, causing them to start working again, only instead of flowing with blood, they flowed with a “blood substitute.” Some of the cells regained metabolic activity and even responded to drugs. Electrical activity was detected in some of the neurons taken from slices of the animals’ treated brain tissue.
The research is in the very earliest stages and it’s not clear what impact, if any, the findings may have on the treatment of brain injuries. But theoretically, the discoveries seem to suggest that it may be possible to recover parts of the brain after death.
Nita A. Farahany, a bioethicist and law professor at Duke University, said:
“We had clear lines between ‘this is alive’ and ‘this is dead.’ How do we now think about this middle category of ‘partly alive’? We didn’t think it could exist.”
The results also offer hope for people who have lost brain function due to injury or stroke. Those considered too far-gone may not beyond help after all. As well, new treatments for conditions like Alzheimer’s disease could come from the experiment.  
But before any of this science can be applied in the real world, there are tricky ethical matters to maneuver, including the potential impact on organ donation protocols. 
Jonathan Moreno, a bioethicist at the University of Pennsylvania, said: 
“This is wild. If ever there was an issue that merited big public deliberations on the ethics of science and medicine, this is one.”
If you have a weak stomach, you might want to sit this part out.
For the experiment, researchers acquired the brains of 32 pigs that had been slaughtered 4 hours earlier. Over the course of 6 hours, the scientists infused the brains with a mixture of synthetic fluids designed to stop cells from breaking down and restore cellular functions, such as metabolic activity. 
The team was successful in its task. They successfully halted the break-down of the neurons and revived their function, allowing the brains to continue to consume oxygen and glucose.
In fact, the neurons showed “spontaneous synaptic activity,” meaning that the neurons were capable of sending out signals, and the cells responded to external electrical stimulation. When cells from the treated brains were examined under a microscope, the scientists found that they had regained the shape of living cells.
The pigs were still very much dead, but the experiment rattled the scientists’ notions about the fragility of the brain.
As for the more immediate ethical concerns, the researchers emphasized that live animals were not used in the experiment, and a chemical was used to ensure the brains would not have any risk of awareness.
Details of the experiment are published in the journal Nature.