The BRAIN Initiative and neuroscience research at large is celebrating an important milestone in April: A Yale School of Medicine researcher has published a report in Nature showing that his team has restored circulation and some cellular functions to pig brains four hours after the animals were killed, Live Science previously reported. Researchers were able to challenge the commonly held belief that brain cells are irreversibly damaged after the heart stops beating. It was not the researchers' intention to observe signs of consciousness in brain tissue, and they didn't make any attempts to do so; on the contrary, they injected pig brains with chemicals that mimicked blood flow while blocking neurons from firing. Scientists confirmed that they did not bring the pig brains back to life. Their cellular activity, however, was restored.