The ocular dominance columns cover the primary (striate) visual cortex, with the exception of monocular regions of the cortical map corresponding to peripheral vision and the blind spot. If the columns corresponding to one eye were colored, a pattern similar to that shown in the accompanying figure would be visible when looking at the surface of the cortex. However, the same region of cortex could also be colored by the direction of edge that it responds to, resulting in the orientation columns, which are laid out in a characteristic pinwheel shape. Similarly, there are columns in the cortex that have high levels of the protein cytochrome oxidase. These are called cytochrome oxidase "blobs" because of their scattered blob-like appearance.