Brain power.

Instead, it seems to me that it will be more practical to make silicon-based AIs mimic biological brains than to turn biological brains in vats into AIs. Perhaps we should be worrying about the welfare of future AIs just as much as we do about how AIs will affect human welfare in the future. So the idea is that living brains, or at least living brain tissue, could be much more efficient than silicon-based AI for some tasks. [Extracted from the article]