Figure 1.

The association between white-matter hyperintensities (WMHs) and cognitive impairment: insights from imaging. Upper left: Interstitial fluid increase leads to WMHs and affects the normal-appearing white matter (NAWM) around it. Patients with WMHs have greater blood-brain-barrier leakage than do controls in the WMHs, NAWM, and cortical gray matter. Upper middle: WMHs progress, leading to secondary cortical thinning and possibly white-matter tract lesions in the NAWM and WMHs. Upper right: WMHs are present, incident lacunae might appear, secondary cortex is thinned, long-tract degeneration worsens, and major attentional networks and their hubs have been injured. (4) The three commonly studied attention networks and their hubs are interrelated. The default-mode network (DMN) includes the medial prefrontal cortex (mPFC) and posterior cingulate cortex (PCC) as major hubs. The frontoparietal control network (FPCN) includes the dorsolateral prefrontal cortex (dLPFC) and the posterior parietal cortex (PPC) as major hubs. The dorsal attentional network (DAN) includes the frontal eye fields (FEF) and the area around the intraparietal sulcus (IPS) as major hubs [29].