I spent my childhood inside my head. There were probably people around, but I was busy being Nancy Drew, or a tragic heroine looking out the car window during a sad song.
(Heroine, that's the word, but I am plunged into a plethora of really weak paperback novels stored in my head, in which one of the characters struggles with a terrible drug addiction until finally deciding to follow Jesus, inside a chapel with stained glass windows and a wise black man. In the rain. More than one book.)
All that to say, I was imaginative, and often wondered if the rest of the world was real, or if it was only me. If I let myself think about that now, I still get kinda weirded out.