It's genetic I suppose, a small percentage of the human population has always gone their "own" way, heard and seen things a bit different than the rest, gained a different perspective on things. They tend to be better people readers, look at the bigger picture, small details are not important, but things and experiences which center around emotion generally are retained. These people are generally true picture thinkers, they generally exclusively generate all thought in pictures. Most individuals think in a combination of words and pictures.