The functional hierarchy of the task-positive networks indicates a core control system of top-down regulation in visual attention

The cingulo-opercular network (CON), dorsal attention network (DAN), and ventral attention network (VAN) are prominently activated during attention tasks. The function of these task-positive networks and their interplay mechanisms in attention is one of the central issues in understanding how the human brain manipulates attention to better adapt to the external environment. This study aimed to clarify the CON, DAN, and VAN's functional hierarchy by assessing causal interactions. Functional magnetic resonance imaging (fMRI) data from human participants performing a visual-spatial attention task and correlating Granger causal inflluences with behavioral performance revealed that CON exerts behavior-enhancing in- flluences upon DAN and VAN, indicating a higher level of CON in top-down attention control. By contrast, the VAN exerts a behaviordegrading inflluence on CON, indicating external disruption of the CON's control set.