The term area d31 refers to one of four parts of the dorsal posterior cingulate cortex.The other parts are area 23d of Vogt, area 23c of Vogt, and area d23. In the human it is located in the most rostral part of the precuneus. It is caudal to area d23 and dorsal to area v31 of the ventral posterior cingulate cortex. It is topologically equivalent to the entire area 31 of the macaque, which has no area v31 ( Vogt-2012 ). It may have partial equivalence to the retrosplenial area of the rat ( Swanson-2004 ) and the mouse ( Hof-2000 ).