A, the brain, when exposed carefully and accurately, is a remarkably beautiful structure. The arteries, veins, gyri, and sulci are organized in a complex array. The frontal convexity is made up of the superior, middle, and inferior frontal and precentral gyri. The parietal convexity is composed of the postcentral gyrus and the superior and inferior parietal lobules. The inferior parietal lobule is made up of the supramarginal and angular gyrus. The temporal convexity is composed of the superior, middle, and inferior temporal gyri. The occipital convexity is formed by the superior and inferior occipital gyri. B, anterior view. The superior and middle frontal gyri are separated by the superior frontal sulcus. The inferior frontal sulcus courses between the middle and inferior frontal gyri. The veins from the anterior part of the hemisphere are directed backward to reach the superior sagittal sinus. A large venous lacunae extends over the superior margin of the frontal lobe adjacent to the superior sagittal sinus. C, posterior view of the hemisphere. The lateral occipital sulcus divides the lateral aspect of the occipital lobe into the superior and inferior occipital gyri. The veins from the occipital convexity are directed forward to enter the superior sagittal sinus. The posterior part of the parietal lobe is divided by the intraparietal sulcus into the superior and inferior parietal lobules. (Images courtesy of AL Rhoton, Jr.)