The term lateral occipital sulcus refers to a horizontal groove on the lateral aspect of the occipital lobe of human cerebral cortex. It separates the middle occipital gyrus into superior and inferior parts. In some cases it intersects the lunate sulcus of the macaque caudally ( Duvernoy-1992 ). Some authors regard the lunate sulcus to be part of the the lateral occipital sulcus ( Van Essen Lab-2002 ). Equivalent structures are not found in the macaque or in the smooth cerebral cortex of the rat and mouse ( NeuroNames ).