Scientists generally believe brain organoids — 3D aggregations of tissue that mimic some of the structures of the brain — are too simple to support consciousness. But as brain organoids become more sophisticated, there's a theoretical possibility that some may cross that threshold someday.
The brain organoids that have been made so far typically represent just one part of the brain at a time. They are used to study brain development and diseases, as well as drug side effects, without requiring animals or human brains.
