Familiar objects often look unfamiliar when you view them upside down.  After all, the visual information that your left brain automatically applies to certain objects is no longer available when you look at them from a new perspective.

When your left brain can't name the various parts of a particular subject, it gets confused and eventually gives up trying to identify that subject - which is when the right brain jumps in and takes over. The right brain sees the lines of your subject differently than the left brain sees them. It focuses on the way the lines curve and how they create shapes ans spaces within the boundaries of your view-port instead of trying to classify the lines and shapes as belonging to a particular object.