The parieto-occipital sulcus (or parietooccipital fissure) is a deep furrow, anterior to the cuneus, that separates the occipital and the parietal lobes. Only a a small part (the lateral part) of the parieto-occipital sulcus is seen on the lateral surface of the hemisphere, its chief part (the medial part) being on the medial surface.
- The lateral part of the parieto-occipital sulcus is situated about 5 centimeters (cm) in front of the occipital pole of the hemisphere, and measures about 1.25 cm. in length.
- The medial part of the parieto-occipital sulcus (Fig. 727) runs downward and forward as a deep cleft on the medial surface of the hemisphere, and joins the calcarine fissure below and behind the posterior end of the corpus callosum. In most cases it contains a submerged gyrus. The parieto-occipital sulcus marks the boundary between the cuneus and precuneus, and also between the parietal and occipital lobes.