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.
During anesthetic-induced unconsciousness, two temporal features of brain activity—long-range temporal correlations (measured by power-law exponent) and temporal variability (measured by standard deviation)—both decrease globally across the brain compared to wakefulness. The spatial relationship between these two features becomes altered, or 'decoupled,' primarily due to changes in the spatial pattern of long-range temporal correlations rather than temporal variability. This suggests that the topographical organization of long-range temporal correlations is crucial for maintaining optimal neural dynamics during normal consciousness, supporting the temporo-spatial theory of consciousness.