The term external cingulate gyrus refers to a narrow curved convolution found on the mesial aspect of the superior frontal gyrus (SFG) in the approximately 35% of humans with a paracingulate sulcus. Identified by dissection, it parallels the anterior cingulate gyrus (ACG), from which it is separated by the cingulate sulcus (cgs). It is bounded externally by the paracingulate sulcus ( Vogt-1995 ). It is not found in the macaque ( Paxinos-2009a ), nor in the smooth cortex of the rat and mouse ( NeuroNames ). Updated 22 Aug 2024.