They're grown from stem cells. Neuro-ethics (especially the ethics around using brain organoids) is an entire field of research. Although brain organoids exhibi

They're grown from stem cells. Neuro-ethics (especially the ethics around using brain organoids) is an entire field of research. Although brain organoids exhibit neural connections and electrical activity, they have so far failed to form even basic synaptic circuits — without which consciousness is probably impossible. But of course we should take every precaution to ensure that they DON'T form consciousness. But that's still a ways away.