The idea of turning your skin cells into brain cells may sound like mad science, but in fact many of the body’s cells still retain a latent ability to transform into other types of cells, so long as they receive the right kinds of biological coaxing. Skins cells have proven to be particularly malleable in this way, and in the past year researchers have learned to convert skin cells into heart cells, blood cells and liver cells. This is the first time, however, that functioning neurons have ever been created in this way.