What is known about the information that's passed upwards within the neocortex?
Your guess 1 basically sounds like habituation:

https://en.wikipedia.org/wiki/Habituation

Per your clarification in your comment, 2 sounds like you are generally talking about the role of prediction error in learning. There's a lot of work on this. Neural network models generally learn by modifying the connection strengths in response to error. The most well-known algorithm for this is known as backpropagation. Although this is an error signal propagating down a network, not up it, as you proposed. There's also the Rescorla-Wagner model of learning, another example of error-driven learning.

3 sounds like top-down processing:

https://en.wikipedia.org/wiki/Top-down_and_bottom-up_design#Neuroscience_and_psychology

Regarding 4, neural firing patterns definitely settle into attractors. This has been pretty extensively modeled:

http://www.scholarpedia.org/article/Attractor_network