If one thing makes you think of another thing, you form a connection between them in your mind. The more connections you have, the better access you have to cross-connections. The more things something can remind you of, the more you know about it, or are learning about it.
"As students develop their visual literacy, they begin to understand that every visual choice the artist has made, every detail regarding subject and color and composition, conveys information that informs the reader." (from "The Power of Pictures: Creating Pathways To Literacy Through Art")