Seems a bit impossible if one hadn't seen any zombie movie or TV show in the last few months given its popularity nowadays, but the concept of coming back to life after death still seems to be far-fetched.
Yesterday, several researchers from Yale University made all these seem plausible. The cellular activity was restored to pigs' brains ten hours after their death. This is with the help of an artificial system known as BrainEx - 'a chamber with specially designed blood replacement fluid that pumps through the blood vessels, delivering oxygen, sugar and other sustaining ingredients at body temperature to keep the brains operating.' (Nature, 2019)
The decapitated pigs were from a slaughterhouse and according to the authors, not one animal died for the study. Immediately after decapitation, about 300 pigs were put on ice and transported to a Yale University laboratory where their brains were surgically removed and placed in BrainEx.
Within six hours of being in the BrainEx system, analyses of the fluid showed cellular respiration occurring; it showed active metabolism.
Several scientists expressed excitement and even disbelief with the results, but ethical concerns were raised as well. "This is a huge breakthrough," says ethicist and legal scholar Nita Farahany of Duke University. "It fundamentally challenges existing beliefs in neuroscience. The idea of the irreversibility of loss of brain function clearly isn't true."
To ease these concerns, neuroscientist Nenad Sestan stated that, "This is not a living brain, but it is a cellularly active brain", he also made assurances that the research "will not backfire". This is true since they were only able to induce cellular metabolism and prevent cell death but the brains showed no signs of widespread neural activity indicating some level of awareness. This is due to the fact that a drug that dampens or blocks neuronal activity was included in the preservative solution because researchers thought the cells would be better preserved if their activity was minimized.
According to researcher Stefano Daniele admits "we cannot speak with any scientific certainty" as to whether consciousness could be restored to the brains without the blocker, since "we did not run those experiments."
But bioethicist Stephen Latham also commented that "It was something the researchers were actively worried about," explaining the researchers had a plan of action in place to shut down the experiment immediately with "anesthesia and cooling" should the pig brains get too excited.
The technique offers a new way to study animal brains in labs, experiments that might yield insights into countering and better treating human brain damage caused by strokes or other injuries, but it is also placing the practice of extracting organs for transplant from brain-dead patients in question - as well as current protocols regarding the handling of (possibly revivable) dead tissue from humans and animals alike.