In this Opinion article, we discuss how integrated information theory accounts for several aspects of the relationship between consciousness and the brain. Integrated information theory starts from the essential properties of phenomenal experience, from which it derives the requirements for the physical substrate of consciousness. It argues that the physical substrate of consciousness must be a maximum of intrinsic cause–effect power and provides a means to determine, in principle, the quality and quantity of experience. The theory leads to some counterintuitive predictions and can be used to develop new tools for assessing consciousness in non-communicative patients.
At a glance
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- Supplementary information S1 (figure) (284 KB)
Axioms and postulates of IIT.
- Supplementary information S2 (box) (83 KB)
- Supplementary information S3 (figure) (189 KB)
Integrated information, neuroanatomy and neurophysiology.
- Supplementary information S4 (box) (785 KB)
Neuronal bistability impairs information integration during slow wave sleep
- Supplementary information S5 (box) (246 KB)
IIT and other theories of consciousness