You can be and do anything you want in art. Be methodical or totally spontaneous, follow a system or create freely. There are really no set of rules, only a differing appreciation of beauty. In this sense, there is no error. You are not breaking any natural laws, you are not putting anyone in danger by creating in a certain way. You are not erring in any way; you are just creating.
Furthermore, the context you are using to talk about the brain and the mind is as if you are certain they are distinct and what their distinction is. Perhaps, subconscious/unconscious or superconscious mind would be more correct in this case. I don't think that we tap on knowledge hidden on some deeper level of consciousness to produce music, though being spiritual I do believe in music "divinely inspired". If you sit at the piano and you play a scale, you will have created music. You are seeing music with a certain mysticism. I will agree that its effects can be profound on the human mind and psyche, but other than that I fail to see any formulas or hidden codes hidden in our deeper consciousness, DNA or whatever. Even if it is true, I can't possibly know...