From the DishBrain paper (Kagan et al., 2022) — the one where cultured neurons learned to play Pong:
Two interrelated processes are required for sentient behavior in an intelligent system. Firstly, the system must learn how external states influence internal states via perception and how internal states influence external states via action. Secondly, the system must infer from its sensory states when it should adopt a particular activity and how its actions will influence the environment.