On a similar note about tuning in to unconscious clues, I observed something like that during my instrument flying training. I was on my long cross country with an instructor. I couldn't see out the window at all, because of the goggles I wore to simulate instrument flying conditions. But all of a sudden I was having a much harder time staying in control- I told my instructor this, and he said we had flown into a cloud. Apparently the sun shining on the instrument panel was enough to clue me in unconsciously.