The landmarks used to establish the borders of each lobe are shown here. The central sulcus lies about halfway between frontal and occipital poles and is significantly deeper than adjacent sulci. The lateral fissure differs from a sulcus in that it was created as tissue migrated in an arc-like fashion to form the temporal lobe. The pre occipital notch is a rather predictable indentation in the surface of the brain, and the parieto-occipital sulcus is a very constant and deep sulcus, present on the medial surface of the hemisphere. The anterior border of the occipital lobe is a line drawn between the pre occipital notch and the upper end of the parieto-occipital sulcus.