PCC, inferior parietal lobe middle is rear half of cingulate cortex, brain region around corpus callosum (neural fibers between 2 hemispheres of brain). Corresponding location to Brodmann areas 23 and 31. Research found differences between activity in dorsal and ventral PCC

PCC, a key default mode network (DMN), a network of brain regions related to self-referential processing. Accordingly, PCC is involved in processing personally relevant words and information and is active during daydreaming and mind-wandering. PCC, like other areas of DMN, is often found to be less active during attention-demanding tasks. Decreased ability to down-regulate PCC activity during tasks is associated with lapses in attention