The term frontal lobe refers to one of six divisions of the cerebral cortex defined by dissection in the human ( Carpenter-1983 ) and the macaque ( Martin-2000 ). The most rostral of the lobes, it is separated from the parietal lobe by the central sulcus, from the temporal lobe by the lateral fissure, from the superior frontal gyrus4 by the cingulate sulcus, and from the inferior rostral gyrus1 by the superior limiting sulcus. In the human the frontal lobe is composed of two groups of gyri and seven individual gyri. The groups are the transverse frontopolar gyri and the orbital gyri. Individual gyri on the dorsolateral surface of the cerebral hemisphere include the superior frontal gyrus, the middle frontal gyrus, the inferior frontal gyrus and the precentral gyrus; those on the mesial side of the hemisphere include part of the superior frontal gyrus, the superior rostral gyrus, the inferior rostral gyrus, and the straight gyrus. The frontal lobe of the macaque is the same except that it lacks transverse frontopolar gyri, a superior rostral gyrus, and an inferior rostral gyrus. Equivalent structures are not found in the smooth cerebral cortex of the rat or mouse ( NeuroNames ).