Neural signs and mechanisms of consciousness: Is there a potential convergence of theories of consciousness in sight?

Various theories of the neural basis of consciousness propose diverse neural signs and mechanisms. This review asks whether that diversity is real or whether theories share basic ideas that could converge. It compares neural signs, measures, and mechanisms across theories, showing that different theories focus on distinct aspects of neural activity—stimulus-related, prestimulus, and resting state—and on distinct features of consciousness. The mechanisms may partly complement each other. The authors conclude that the different theories concern distinct aspects of neural activity and consciousness that may be integrated and nested within the brain's overall temporo-spatial dynamics.

Study at a glance

Abstract

Various theories for the neural basis of consciousness have been proposed, suggesting a diversity of neural signs and mechanisms. We ask to what extent this diversity is real, or whether many theories share the same basic ideas with a potential for convergence towards a more unified theory of the neural basis of consciousness. For that purpose, we review and compare the various neural signs, measures, and mechanisms proposed in the different theories. We demonstrate that different theories focus on neural signs and measures of distinct aspects of neural activity including stimulus-related, prestimulus, and resting state activity as well as on distinct features of consciousness. Therefore, the various mechanisms proposed in the different theories may, in part, complement each other. Together, we provide insight into the shared basis and convergences (and, in part, discrepancies) of the different theories of consciousness. We conclude that the different theories concern distinct aspects of both neural activity and consciousness which, as we suppose, may be integrated and nested within the brain's overall temporo-spatial dynamics.