I didn't say anything about external sources of stress. I said sources of stress. External events cause stress in the body which can be measured physiologically and neurologically. The mind can be a contributing factor but it is absolutely not necessary. Injuries that you're entirely unconscious of can cause significant levels of stress which are measurable.
No, I think this is meaningless. What you're refering to is the brain. Positing a subcoscious mind adds nothing to the explanatory model since everything this supposed entity does is already done by the brain and pretty well understood at that. Occam's razor. You're stuck in old Cartesian metaphysics (dualism and parallelism) which has been superceded by better scientific undetstandings for quite a while now.
