Functional connectivity within two brain networks plays distinct roles in disorders of consciousness. Connectivity in the salience network, particularly between the supragenual anterior cingulate cortex and left anterior insula, was reduced in patients with unresponsive wakefulness syndrome compared to those in a minimally conscious state or fully conscious brain-lesioned patients. This connectivity correlated with behavioral signs of consciousness. In contrast, connectivity in the default-mode network, specifically between the posterior cingulate cortex and left lateral parietal cortex, was weaker in patients with unresponsive wakefulness syndrome who did not recover compared to those who later emerged from this state, suggesting this network predicts recovery of consciousness.
Patients with disorders of consciousness (DOC) show reduced brain activity in midline regions (anterior and posterior cingulate cortex) during self-referential thinking tasks compared to healthy individuals. The degree of signal reduction in the perigenual anterior cingulate cortex predicts their level of consciousness. These same midline regions also display abnormal resting-state functional connectivity and low-frequency fluctuations. The findings link self-referential processing, resting-state brain activity, and consciousness, suggesting that neural abnormalities in these areas contribute to DOC.