The occipital lobe is one of the four major lobes of the cerebral cortex in the brain of mammals. The occipital lobe is the visual processing center of the mammalian brain containing most of the anatomical region of the visual cortex.The primary visual cortex is Brodmann area 17, commonly called V1 (visual one).hus, the occipital lobe is defined as the part of the cerebral cortex that lies underneath the occipital bone. (See the human brain article for more information.). The lobes rest on the tentorium cerebelli, a process of dura mater that separates the cerebrum from the cerebellum.