Conscious Processing and the Global Neuronal Workspace Hypothesis

Abstract

Mashour et al. review more than two decades of research on the global neuronal workspace theory of conscious processing, examine recent data related to unconscious states, and present a synthesis that links conscious access, attention, and working memory.

More than just front or back: Parietal-striatal-thalamic circuits predict consciousness level

“…GNW, consciousness depends on an "ignition" process in which information becomes globally available through top-down signals from frontal cortex (1,2). In HOT, consciousness depends on frontal cortex supporting a higher-order thought about a sensory experience (3,4).…”

A neural representation of invisibility: when stimulus-specific neural activity negatively correlates with conscious experience

“…Our results challenge this account, as stimulus-specific neural activity positively correlated with subjective invisibility . Our findings are also difficult to accommodate within the global neuronal workspace theory (GNWT) of consciousness 31 . According to GNWT, attention typically acts as a gateway to conscious access, enhancing stimulus representations for wider broadcasting, and awareness positively correlates with the strength of sensory-specific information 32 .…”

Hierarchical disruption in the cortex of anesthetized monkeys as a new signature of consciousness loss

“…These hierarchical changes find their common ground in cingulate and parietal regions. It may imply, that under the hierarchical hypothesis, both theories are complementary to each other, and approaching compatible aspects of the same conscious phenomenon (Aru, Bachmann, Singer, & Melloni, 2012;Block, 2005;Dehaene et al, 2014;Tagliazucchi, 2017;Mashour et al, 2020 ). This solves in part the requirement of a desirable common and global mechanism to explain how brain dynamics are similarly affected under anesthetics, at the same time than recovering the specificity of affecting and modulating correlations and couplings of brain regions.…”

“…Recent studies suggest dynamical disruptions on brain activity during general anesthesia, sleep and disorders of consciousness ( Dehaene & Changeux, 2011 ;Mashour et al, 2020 ). Nevertheless, whatever the level of consciousness, the resting-state brain activity displays highly organized coherent networks (Biswal, Yetkin, Haughton, & Hyde, 1995;Buckner, Andrews-Hanna, & Schacter, 2008;Fox et al, 2005;Fransson, 2006;Vincent et al, 2007).…”