Abstract
Models of cognitive function typically focus on the cerebral cortex, ignoring functional links to subcortical structures. This view neglects the highly-conserved ascending arousal system’s role and the computational capacities it provides the brain. In this study, we test the hypothesis that the ascending arousal system modulates cortical neural gain to alter brain dynamics’ low-dimensional attractor landscape. Our analyses of spontaneous functional magnetic resonance imaging data and phasic bursts in both locus coeruleus and basal forebrain demonstrate precise time-locked relationships between brainstem activity, low-dimensional energy landscapes, network topology, and spatiotemporal travelling waves. We extend our analysis to a cohort of experienced meditators and demonstrate locus coeruleus-mediated network dynamics were associated with internal shifts in conscious awareness. Together, these results present a novel view of brain organization that highlights the ascending arousal system’s role in shaping both the dynamics of the cerebral cortex and conscious awareness.
One Sentence Summary Fluctuations in brainstem arousal structures coincide with whole-brain topological network fluctuations and low-dimensional state space dynamics that facilitate alterations in attentional awareness.
Competing Interest Statement
The authors have declared no competing interest.