Back From the Dead

We consider dying to be irreversible. When someone passes away, their death is the final goodbye—the last moment one has with that person. It is only in poorly written sci-fi movies that we imagine a place where humans can come back to life. However, a world where revival from death is possible might be closer than you think. This past April, researchers at Yale University published a study in the scientific journal Nature that took a huge step towards making death a second thought.In the paper, the team of scientists explained how they restored some functionality to a pig’s brain for around six hours, just four hours after the pig’s death. Before, in the scientific world, many scientists have been able to reuse postmortem brain cells and study them by culturing them on a petri dish. But Nenad Sestan, the senior author of the paper and a professor of neuroscience at Yale, wanted to dig deeper. He and his team immersed the brain in a system they developed known as BrainEx, comprised of pumping a fluid that can carry oxygen through major blood vessels in the brain with a series of computer-controlled filters and pumps.When they compared the brain connected to BrainEx with a brain filled with a neutral fluid, the team found that the developed system was better able to sustain neural cell integrity, with a much-reduced cell mortality rate and a more intact cell structure. They even observed the return of certain cellular functions such as the production of immune cells, or gilia, that had an inflammatory reaction when a bacterial-like molecule was introduced. The scientists did make it clear that many essential functions of the brain were still missing. As co-first author Zvonimir Vrselja stated, “at no point did we observe the kind of organized electrical activity associated with perception, awareness, or consciousness.”  Still, many of the researchers were surprised by the results of the study. Researcher Stefano Daniels described the experiment as ”a shot-in-the-dark project."The study also found another way to analyze the brain. Before, scientists had struggled with finding ways to study any large mammalian brain in full detail. The only way scientists could analyze large sections of the functioning brain had been through 2-D cross-sections. Now, as techniques develop from systems like BrainEx, we can see a more effective understanding of many neurological topics.Hopefully, this study will encourage others to research both how to bring people back from the dead and how we can prevent and treat ischemic injuries such as strokes or other brain disorders. Specifically, according to Sestan, the scientists hope “to better understand how brain cells react to circulatory arrest and if we can intervene and salvage these cells.”In the long term, this study can help us better understand the inner workings and circuitry of our brain. If we can eventually look at a fully functioning brain in three dimensions, we can discover the full context of connected circuits firing throughout the brain. Scientists can also analyze the intricacies of neurodegenerative diseases such as Alzheimer’s by tracking the toxic proteins that move throughout the brain. We can only track these toxins, however, if we can analyze the brain in real time, a problem that research similar to this study can solve.Scientists will face a large barrier if they want to continue research with postmortem bodies: an ethical boundary. In this particular study, the team made sure to fall within the current existing frameworks in bioethics. “Restoration of consciousness was never a goal of this research,” said co-author Stephen Latham, director of Yale’s Interdisciplinary Center for Bioethics. “The researchers were prepared to intervene with the use of anesthetics and temperature-reduction to stop organized global electrical activity if it were to emerge.” Going forward, neuroscience and bioethics alike might have to change these current ethical frameworks to adapt to the new discoveries. Is it wrong to return someone dead unwillingly back to life for science, even in order to better the rest of society? These are questions that will be debated in the years to come.