The term area 31pd refers to a part of posterior cingulate cortex located caudally in the posterior cingulate gyrus. It is bounded caudally by area 7m, dorsally by area PCV, rostrally by area 31a and ventrally by area v23ab and area 31pv. It is considered one of three parts of area 31 of Vogt-2009. The others are area 31pv and area 31a. Defined in the human by multiple criteria, it is fMRI-activated in BODY, FACE and STORY tasks. It is deactivated in PLACE and LANGUAGE tasks. Other authors have referred to overlapping parts of the same topological area as 31, 31d and 31v ( Glasser-2016 ).