The term area a24' refers to the part of area 24 that intersects the anterior midcingulate cortex of the human and the macaque. Defined on the basis of multiple criteria, it occupies approximately the middle third of the anterior cingulate gyrus. In the human it consists of four parts: area a24a', area a24b', area a24c'v, and area a24c'd. In the macaque it has only three parts: area a24a', area a24b', and area a24c' ( Vogt-2012 ).