What do you mean by transferring from mind to brain? Is there some sort of duality there that I'm not aware of?
Basically theory makes it easier for you to get the sounds from your imagination onto your medium of choice:
You might have a harmony you like looping around in your head but without knowing what those chords are (how to play them or click them into a sequencer) you're forced to work by trial and error which is slow, frustrating and might never get you there.
If you know the theory you can listen in your head and recognise the sound as a I6/9 to VIb7 or whatever, then putting it into the sequencer is quick and easy. Theory also means you know that looking at those two previous chords there is modal mixture going on (first chord is major, second chord is borrowed from the minor key with the same root) and that opens up other possibilities for where the music goes next.
Knowing how to get to a particular sound with as few obstacles as possible is a good thing. The more sounds you know how to achieve the better.
There's production theory too it just has a shorter history and isn't as codified so people don't get as intimidated or annoyed by it.
If you want something to sound like it's coming from far away you'd lower the volume, cut the high and low freqs (inverse square law, Robinson–Dadson, evolution, babies etc.) + send it through a reverb with little to no pre-delay because if the sound source is distant in the real world you won't hear the direct sound before you hear the reverberations.
You can still just twiddle knobs and jam and see what sounds cool but knowing how to achieve what you have in your head is useful as heck.
Theory isn't rules, it's just saying "how did they do x?"