consciousness, namely the neural correlates of various conscious processes.[22] This more modest goal is
the focus of most scientists working on consciousness.[133] Psychologist Susan Blackmore believes, by
contrast, that the search for the neural correlates of consciousness is futile and itself predicated on an
erroneous belief in the hard problem of consciousness.[134]
A functionalist view in cognitive science holds that the mind is an information processing system, and
that cognition and consciousness together are a form of computation. Cognition, distinct from
consciousness, is explained by neural computation in the computational theory of cognition. The
computational theory of mind asserts that not only cognition, but also phenomenal consciousness or
qualia, are computational. While the computation system is realized by neurons rather than electronics, in
theory it would be possible for artificial intelligence to be conscious.
Integrated information theory (IIT), developed by the neuroscientist and psychiatrist Giulio Tononi in
2004 and more recently also advocated by Koch, is one of the most discussed models of consciousness in
neuroscience and elsewhere.[135][136] The theory proposes an identity between consciousness and
integrated information, with the latter item (denoted as Φ) defined mathematically and thus in principle
measurable.[136][137] The hard problem of consciousness, write Tononi and Koch, may indeed be
intractable when working from matter to consciousness.[15] However, because IIT inverts this relationship
and works from phenomenological axioms to matter, they say it could be able to solve the hard
problem.[15] In this vein, proponents have said the theory goes beyond identifying human neural
correlates and can be extrapolated to all physical systems. Tononi wrote (along with two colleagues):
While identifying the "neural correlates of consciousness" is undoubtedly important, it is
hard to see how it could ever lead to a satisfactory explanation of what consciousness is and
how it comes about. As will be illustrated below, IIT offers a way to analyze systems of
mechanisms to determine if they are properly structured to give rise to consciousness, how
much of it, and of which kind.[138]
As part of a broader critique of IIT, Michael Cerullo suggested that the theory's proposed explanation is in
fact for what he dubs (following Scott Aaronson) the "Pretty Hard Problem" of methodically inferring
which physical systems are conscious—but would not solve Chalmers' hard problem.[136] "Even if IIT is
correct," he argues, "it does not explain why integrated information generates (or is) consciousness."[136]
Chalmers agrees that IIT, if correct, would solve the "Pretty Hard Problem" rather than the hard
problem.[139]
Global workspace theory (GWT) is a cognitive architecture and theory of consciousness proposed by the
cognitive psychologist Bernard Baars in 1988.[140] Baars explains the theory with the metaphor of a
theater, with conscious processes represented by an illuminated stage.[140] This theater integrates inputs
Computational cognition
Integrated information theory
Global workspace theory