Hang on, you say: That doesn’t seem right! If it were the exact same generative models, then when we remember dancing, we would actually issue the motor commands to start dancing! Well, I answer, we do actually sometimes move a little bit when we remember a motion! I think the rule is, loosely speaking, the top-down information flow is much stronger (more confident) when predicting, and much weaker for imagination, memory, and empathy. Thus, the neocortical output signals are weaker too, and this applies to both motor control outputs and hormone outputs. (Incidentally, I think motor control outputs are further subject to thresholding processes, downstream of the neocortex, and therefore a sufficiently weak motor command causes no motion at all.)
As I recall, much of how the brain causes you to do one thing rather than another involves suppression of signals. As in, everything in the brain is doing it’s thing all the time, and how you manage to do only one thing and not have a seizure is that it suppresses the signals from various parts of the brain such that only one is active at a time.
That’s probably a bit of a loose model and doesn’t exactly explain how it maps to particular structures, but might be interesting to look at how this sort of theory of output suppression meshes with the weaker/stronger model you’re looking at here built out of PP.
As I recall, much of how the brain causes you to do one thing rather than another involves suppression of signals. As in, everything in the brain is doing it’s thing all the time, and how you manage to do only one thing and not have a seizure is that it suppresses the signals from various parts of the brain such that only one is active at a time.
That’s probably a bit of a loose model and doesn’t exactly explain how it maps to particular structures, but might be interesting to look at how this sort of theory of output suppression meshes with the weaker/stronger model you’re looking at here built out of PP.