Posterior integration and thalamo-frontotemporal broadcasting are impaired in disorders of consciousness

The study of the brain9s dynamical activity is opening a valuable source of assistance for the clinical diagnosis of patients with disorders of consciousness (DOC). For example, dysfunctional spread of naturalistic and synthetic stimuli has proven useful to characterize hampered consciousness. However, understanding of the mechanisms behind loss of consciousness following brain injury is still missing. Here, we study the propagation of endogenous and in-silico exogenous perturbations in patients with DOC, based upon directed and causal interactions estimated from resting-state fMRI. We found that patients with DOC suffer decreased capacity for neural propagation and responsiveness to events. Particularly, that loss of consciousness is related to the malfunctioning of two neural circuits: the posterior cortical regions failing to convey information, in conjunction with reduced broadcasting of information from subcortical, temporal, parietal and frontal regions. These results seed light on the mechanisms behind DOC, thus opening new possibilities for clinical applications.