The network model of delirium.

The coordinated function of brain networks underlies consciousness, attention and reality testing, all of which are impaired in delirium. The default-mode network, salience network, frontoparietal control network and dorsal attention network are brain networks with integral roles in the maintenance and modulation of the aforementioned functions. Multiple lines of evidence point to their dysfunction in delirium. The convergence of neurotransmitter changes, neuroendocrine and inflammatory stressors on brain networks disrupts bottom-up and top-down attentional control. Neuroimaging and neuroanatomy correlates are potentially consistent with this hypothesis. Overall, this model appears to have significant utility in connecting the seemingly disparate precipitants of delirium while accounting for the clinical manifestations of the syndrome.