The tabs Ernest n show how Ernest n sees his world: 12 pixel vision, 3x3 tactile matrix, taste fish. The spatial construct represents Ernest's representation of his surrounding environment. We are still investigating how Ernest can represent space and discover spatial regularities. See the Ernest 10.3 post in the blog for more information.
You can interact with Ernest by inserting or removing objects in the scene. You can even insert other Ernests. So far, however, Ernests have no particular interest into each other.