The posterior cingulate cortex (Brodmann area, BA 23) is the hub of the default mode network (DMN). Moreover, its network connectivity decreases early in Alzheimer disease. The anterior cingulate cortex (BA 24) is connected to networks such as the DMN, working memory network (WMN), and salience network (SN) and plays a role in network coordination. The subgenual anterior cingulate cortex (sgACC) on the rostral region of the anterior cingulated cortex is suggested to be associated with depression.