SMD and visual stimulation

My daughter was diagnosed with complex motor stereotypy when she was 3 - now almost 5. I am curious about the link between visual processing and stereotypy. Hers reveals itself when she is daydreaming or letting her mind wander, so places like at home, in the car, school lunch table or at the dinner table, etc. At school her teachers comment that they rarely see it in class, because she is so engrossed in activity. This is particularly true when being read to or told an oral story or seeing a play, etc. It seems for her there is a link between taking in information visually - looking at a book, looking at her teachers or friends faces, etc. Any thoughts on this?