Major anatomic features of the midline supratentorial brain. The central sulcus, on the lateral cerebrum, is demarcated with yellow pins. The insula, deep (lateral) to the midline, is demarcated with black pins. The cingulate gyrus lies just superior to the corpus callosum, and the cingulate sulcus runs adjacent to the cingulate gyrus. The posterior end of the cingulate sulcus ends in the marginal ramus. Anterior to this marginal ramus is the paracentral lobule – the continuation of the precentral and postcentral gyri; therefore, the sulcus that splits the paracentral lobule is the central sulcus. The precuneus is the medial portion of the superior parietal lobule on the medial surface of the brain. The cuneus and the lingual gyrus are the medial portions of the occipital lobe; the parieto-occipital sulcus separates the precuneus from the cuneus, and the calcarine sulcus separates the lingual gyrus from the cuneus. (Image courtesy of AL Rhoton, Jr.)