In a neurotypical brain, when the TPN is turned on and you’re on task, the DMN is turned off. But in the ADHD brain, the fMRI shows that when the TPN is turned on, the DMN is turned on as well, trying to muscle its way in and pull you into its grasp, thereby distracting you. In ADHD, therefore, the DMN competes with the TPN, which in most people it does not do.