Hello everyone.
After re-reading NoPR and making some highlights, I encountered a single sentence that was quite the breakthrough for me on this topic. Here it is:
In somewhat the same manner, your physical brain is a doorway that triggers activity in your mind. Your beliefs then are largely responsible for the areas of the brain that you activate, and for the resulting nonphysical action of the mind.
Session 671, Chapter 20, The Nature of Personal Reality
I feel like this says everything. Mind is of course the origin, but mind creates brain which can also again shape the mind. Thoughts? Do you guys find this quote as evocative and helpful as I did?