Scientists bring pigs’ brains back from dead

The experiment has blurred the line between life and death, and provoked excitement and horror in equal measure. Does this mean we will one day be able to reverse death? Should we want to? Thirty-two pigs heads were laid on a slab in a laboratory. The pigs had been slaughtered four hours earlier. Then their heads were severed from their bodies. They were, without question, dead. But not for long. When the scientists pumped the heads with artificial blood, some brain cells started functioning again. In fact, certain regions of the brain were behaving as if they had never died. However, the scientists were unable to restore brain-wide electrical firing, which means the brains did not regain consciousness. “They could not think. They could not feel,” explains science writer Mark Ritter. “But within them, you could see the signs of activity.” The findings, which have now been published in the journal Nature, are forcing doctors to re-think the boundary between life and death. It even raises the possibility that we could reverse death entirely. Until the 1950s, a person was considered dead when their body had lost one of three key functions: their heart stopped beating; they stopped breathing, or their brain showed no signs of activity. But then came CPR and ventilators, which could revive the heart and keep the lungs breathing. That left only brain death as the last concrete, irreversible symptom of death. Until now. Could we, one day, reverse brain death in humans? Neuroscientist Nenad Sestan, who led the experiment, believes it would work on the brains of primates, a group which includes humans. He also thinks it could be possible to restore consciousness, perhaps indefinitely. But assuming your body was damaged beyond repair by age, disease or injury, what kind of life would it be? A living hell, according to ethics professor Benjamin Curtis. “You would have to spend the foreseeable future as a disembodied brain in a bucket, locked away inside your own mind without access to the senses that allow us to experience and interact with the world,” he argued in a piece for The Conversation. Even an new, healthy body might not help. Curtis says that, attached to a new body, the brain would be overwhelmed with unfamiliar chemical and electrical signals. “It could send [it] mad,” writes Curtis. Rest in peace? Why are we so concerned with reversing death? Death isn’t evil, it’s natural. Immortal life would eventually make you despondent and bored, having done and seen everything on offer. Life is precious and poignant because we know it isn’t forever. But if we could preserve our bodies and minds in perfect health, how long would you want to live for? A few hundred years? A few thousand? It would mean more time with our families; time to travel the world; time to write a book or learn a language. Doesn’t that sound like heaven? KeywordsConsciousness - When someone is aware of their own body and environment, they are "conscious".