What is the difference between conscious and unconscious action? Unconscious action is autonomous. It is executed according to a set of rules, although the action may be quite complex. Conscious action has a context – the environment, in which it takes place. Conscious action happens only after modelling of consequences. It implies perception of the implications in advance.
Unconscious actions are not remembered, but conscious are. Why? Because the brain cannot predict the result of the modelling: it can predict environment, but it cannot predict its own imagination. So unpredicted experience is recognized as valuable and remembered.
Why do I have only one consciousness in my head? Can I develop two and allow them to communicate? Indeed, if a part of cortex can model, predict, and imagine the environment why it cannot develop its own conscious behaviour? Or maybe we have multiple conscious agents in our head, but they so aligned with each other that they are not distinguishable. Have you ever heard voices in your head?