The term anterior cingulate gyrus (CGGa) refers to one of three components of the cingulate gyrus (CGG) of the superior frontal gyrus4 (LLB) in the human ( Carpenter-1983 ) and the macaque ( Martin-2000 ). The others are the posterior cingulate gyrus (CGGp) and the isthmus of the cingulate gyrus (ICG) ( Carpenter-1983 ). Identified by dissection, the CGGa is a prominent convolution on the mesial aspect of the cerebral hemisphere (CHS). In the human, it lies dorsal to the anterior two-thirds of the corpus callosum (cc) from which it is separated by the callosal sulcus (cas). Rostrally it wraps around the genu of the corpus callosum (ccg) and becomes continuous with the subcallosal gyrus (SCL). In the depth of the cas, the supracallosal gyrus (SCG) partially intervenes between CGGa and the cc. The CGGa is not the same as the anterior cingulate cortex (ACC), which is defined on the basis of internal structure, connectivity and function ( Vogt-2012 ). ACC occupies only the rostral part of the CGGa; the remainder is occupied by midcingulate cortex (MCC). Dorsally CGGa is separated from the superior frontal gyrus (SFG) by the cingulate sulcus (cgs). It is bounded caudally by the posterior cingulate gyrus (CGGp). The junction, which is unmarked topologically, is located at about the level of the central sulcus (cns) on the dorsal surface of the hemisphere. It corresponds to the boundary between cytoarchitectural area 24 anteriorly and area 23 posterior in MCC ( Vogt-2012 ). Considerable confusion in the neuroscientific literature results from attribution of MCCa functions to the CGGa structure. Except for greater complexity of sulcal patterns in the human ( Vogt-1995 ), the CGGa is similar in the macaque ( Vogt-1987 ). It occupies the anterior half of the CGG dorsal to the cc and includes the area topologically equivalent to the SCL of the human . It is bounded rostrally by the straight gyrus (SRG) from which it is partially separated by the rostral sulcus (ros) ( Martin-2000 ). While the rat and mouse share structures equivalent by internal structure to parts of CGGa in primates, a topological equivalent to the gyrus is not found in the smooth cerebral cortex (CTX) of the rat or mouse ( NeuroNames ). Updated 30 Oct 2024.