The term area POS1 refers to one of the more rostral of four areas in the anterior bank of the parieto-occipital sulcus, on the medial surface of the hemisphere, that are transitional between early visual cortex and posterior cingulate association cortex. The others are area DVT, area ProS, and area POS2. Commonly misidentified as a component of retrosplenial cortex, POS1 is bounded caudally by area DVT and area ProS, dorsally by area POS2, rostrally by area RSC, area v23ab and area 7m. It is transitional in the sense that it shares architectural features with areas more rostral and functional features similar to areas more caudal. Defined in the human by multiple criteria, it is involved in the performance of an extensive number of tasks. It is fMRI-activated in PLACE and somewhat activated in MOTOR CUE tasks and deactivated in WORKING MEMORY, BODY, FACES, LANGUAGE, STORY and RELATIONAL tasks ( Glasser-2016 ).