Anesthesiology
September 30, 2010
Pierre Boveroux, Audrey Vanhaudenhuyse, Marie‐Aurélie Bruno et al.
645 citations
Propofol-induced unconsciousness is linked to decreased connectivity within frontoparietal networks (the default-mode and executive-control networks) and between the thalamus and these networks, with a negative correlation between thalamic and cortical activity emerging during unconsciousness. In contrast, connectivity in low-level sensory cortices (auditory and visual networks) is preserved, including their thalamocortical connections. Loss of consciousness is associated with a breakdown of cross-modal interactions between visual and auditory networks. These findings suggest that unconsciousness results from disrupted communication between sensory and higher-order frontoparietal cortices, preventing conscious perception.
Journal of The Royal Society Interface
January 1, 2016
Enzo Tagliazucchi, Dante R. Chialvo, Michael Siniatchkin et al.
210 citations
Loss of consciousness from propofol sedation reduces long-range temporal correlations in frontothalamic brain activity and weakens the link between functional connectivity and anatomical structure. A model based on phase transitions in complex systems reproduces these patterns and also explains the cortex's reduced sensitivity to external stimuli during unconsciousness. The findings suggest that these neural changes are universal across different causes of unconsciousness.
PLoS ONE
June 30, 2014
Enrico Amico, Francisco Gómez, Carol di Perri et al.
115 citations
Functional connectivity of brain areas fluctuates over time, even during anesthesia. By applying point process analysis to resting-state fMRI data from 18 healthy subjects during propofol-induced wakefulness, sedation, unconsciousness, and recovery, the study identified eight distinct co-activation patterns centered on the posterior cingulate cortex (PCC). The core of these patterns remained stable across consciousness levels, but propofol caused region-specific reductions in co-activation, including disconnections of the prefrontal cortex, thalamus, auditory cortex, motor cortex, and visual area. The methodology helps refine characterization of local functional brain changes associated with propofol-induced modulation of consciousness.