The term parietal operculum (OPRpr) refers to the part of the supramarginal gyrus (SMG) of the parietal lobe (PLB), that overlies the caudal portion of the insula (INS) in the human. Rostrally it is separated from the subcentral operculum (OPRsc) by the postcentral sulcus (pocs) ( Ture-1999 ). Identified by dissection,.the posterior one-third of the superior limiting sulcus (slms) separates it from the INS deep in the lateral fissure (ltf). It is not found in the macaque where the OPRsc covers the entire caudal part of te INS ( Mesulam-1985 ). Nor is it found in the smooth cerebral cortex (CTX) of the rat and mouse ( NeuroNames ). Updated 30 Aug 2024.