I absolutely agree that subcortical structures are critical to motivation and behavior. I’m encouraged that you agree that every drive must have termination signal.
I agree that there can be different satisfaction triggers for lizard-level drives. I believe at some level of development there is a recognition of how the pleasurable sensation that a full belly creates is at least a little like other pleasurable sensations, for example, safe sleeping quarters. When the organism is “idle”, it can pursue one of the behaviors on its pleasurable list.
I suggest that in humans there is a more synthetic signal, one that gives rise to the “Aha!” sensation in mental problem solving. This signal promoted the behavior we call curiosity.
I didn’t discuss, but I believe the emergence of the Aha! signal is related to the need to process “mental” objects that emerge in social relationships, the most complex of which seem to be human. It’s not surprising (to me) that only humans might evolve the signal so highly.
My proposition only requires that signal and enough “down-time” from primal drives for the emergence of curiosity.
Curiosity expands the goal map greatly, but the goal map was populated before there was curiosity; before there were brains, organisms had goals.
I see you’ve edited again. Could you maybe please start a new post for new information while we’re typing back and forth?
I also edited for typos.