The study involved high-resolution scans that enabled the researchers to visualize brain connections at submillimeter spatial resolution. This technical advance allowed them to identify previously unseen pathways connecting the brainstem, thalamus, hypothalamus, basal forebrain, and cerebral cortex. Together, these pathways form a “default ascending arousal network” that sustains wakefulness in the resting, conscious human brain.
The researchers found that the default ascending arousal network is comprised of multiple interconnected components, including the reticular formation of the brainstem, the intralaminar thalamic nuclei, the hypothalamus, the basal forebrain, and the cerebral cortex. These structures work together to maintain a state of consciousness and wakefulness.
Furthermore, the study revealed that disruptions or imbalances within this network may underlie various neurological and psychiatric disorders, such as coma, vegetative state, and disorders of consciousness. By understanding the precise architecture and dynamics of the default ascending arousal network, the researchers hope to develop more effective interventions for these conditions.