A Canadian bioethicist says a recent study that restored activity to the brains of dead pigs creates a kind of “grey zone” between life and death.

They can’t proclaim “It’s alive!” just yet — no consciousness was restored — but the Yale University scientists observed neural activity in individual brain cells of pigs several hours after death.

“There’s a growing amount of evidence that this line between life and death is not a sharp line at all,” said University of Toronto bioethicist Kerry Bowman on CTV’s Your Morning. “It could have implications for humans.”

With a “cocktail of cell-rejuvenating compounds,” Yale scientists Stefano Daniele and Zvonimir Vrselja fashioned a makeshift circulatory system in attempts to stimulate brain activity. “A lot of these components are readily available and no one really thought to put them together in a particular manner that could result in this type of study,” said Daniele in a Yale Daily News article.

No animals were harmed for the research, which was published in the journal Nature in April. Instead, the scientists waited for discarded specimens to become available at a local food processing plant. They would rush back to the Yale School of Medicine and remove the pig’s brain and inject the stimuli.

It took years of trial-and-error to refine the research, they added, but they eventually observed electrical activity from individual neurons. The research shows that brain cells may survive longer than thought.

“There really should have been almost no activity at all,” said Bowman on Your Morning, adding that the research does not mean that the definition of brain death is invalid. It is still early days for this type of research, which has not been tested on humans.

“For now, it raises more questions related to, potentially, the validity of brain death,” he said. “It may give energy to the movement of cryopreservation and more people freezing their brains in hopes they could restore function at some point.”

Original Article