ArticleLiterature Review

Theories of consciousness

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Abstract

Recent years have seen a blossoming of theories about the biological and physical basis of consciousness. Good theories guide empirical research, allowing us to interpret data, develop new experimental techniques and expand our capacity to manipulate the phenomenon of interest. Indeed, it is only when couched in terms of a theory that empirical discoveries can ultimately deliver a satisfying understanding of a phenomenon. However, in the case of consciousness, it is unclear how current theories relate to each other, or whether they can be empirically distinguished. To clarify this complicated landscape, we review four prominent theoretical approaches to consciousness: higher-order theories, global workspace theories, re-entry and predictive processing theories and integrated information theory. We describe the key characteristics of each approach by identifying which aspects of consciousness they propose to explain, what their neurobiological commitments are and what empirical data are adduced in their support. We consider how some prominent empirical debates might distinguish among these theories, and we outline three ways in which theories need to be developed to deliver a mature regimen of theory-testing in the neuroscience of consciousness. There are good reasons to think that the iterative development, testing and comparison of theories of consciousness will lead to a deeper understanding of this most profound of mysteries. Various theories have been developed for the biological and physical basis of consciousness. In this Review, Anil Seth and Tim Bayne discuss four prominent theoretical approaches to consciousness, namely higher-order theories, global workspace theories, re-entry and predictive processing theories and integrated information theory.

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... The Lorentz force (EM in general) lacks all specification of "what it is like to be the Lorentz force." There has, more recently, been some success using EM field measurements to quantify and explore the integrated information content (measured level of P-Consciousness) of the vast and real fundamental EM field system of the brain impressed on space as per Supplementary Material A (Koch, 2019; Seth and Bayne, 2022). How can IIT use EM as empirical evidence (thereby proving EM delivers the 1PP) while, in effect, denying that it is EM that is actually delivering the 1PP? ...
... As this article goes to press a new review article has been published listing 22 theories of consciousness, including the EM field theory of consciousness. This evidences a small improvement in the visibility of the EM account of consciousness (Seth and Bayne, 2022). The abstracting-away of the EM basis of the brain (physicsshyness within neuroscience) is a common factor that is the most likely explanation of the observed relative obscurity. ...
... It seems an apt way of forging a path ahead. IIT and its variants have already demonstrated unique progress in "detecting consciousness" using EM field measurements (Koch, 2019;Seth and Bayne, 2022). It may be that IIT's apparent access to deeper insight is actually a result of it being unknowingly involved in the novel (ii) kind of fundamental physics. ...
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Few people tackle the neural or computational basis of qualitative experience (Frith, 2019). Why? One major reason is that science and philosophy have both struggled to propose how we might even begin to start studying it. Here I propose that metacognitive computations, and the subjective feelings that go along with them, give us a solid starting point. Specifically, perceptual metacognition possesses unique properties that provide a powerful and unique opportunity for studying the neural and computational correlates of subjective experience, falling into three categories: (1) Metacognition is subjective: there is something it is like to feel ‘confident’; (2) Metacognitive processes are objectively characterizable: We can objectively observe metacognitive reports and define computational models to fit to empirical data; (3) Metacognition has multiple hierarchically-dependent “anchors”, presenting a unique computational opportunity for developing sensitive, specific models. I define this Metacognition as a Step Toward Explaining Phenomenology (M-STEP) approach to state that, given these properties, computational models of metacognition represent an empirically-tractable early step in identifying the generative process that constructs qualitative experience. By applying decades of developments in computational cognitive science and formal computational model comparisons to the specific properties of perceptual metacognition, we may reveal new and exciting insights about how the brain constructs subjective conscious experiences and the nature of those experiences themselves.
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Consciousness remains a formidable challenge. Different theories of consciousness have proposed vastly different mechanisms to account for phenomenal experience. Here, appealing to aspects of global workspace theory, higher-order theories, social theories, and predictive processing, we introduce a novel framework: the self-organizing metarerpresentational account (SOMA), in which consciousness is viewed as something that the brain learns to do. By this account, the brain continuously and unconsciously learns to redescribe its own activity to itself, so developing systems of metarepresentations that qualify target first-order representations. Thus, experiences only occur in experiencers that have learned to know they possess certain first-order states and that have learned to care more about certain states than about others. In this sense, consciousness is the brain's (unconscious, embodied, enactive, nonconceptual) theory about itself.
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The book offers solutions to two related puzzles. One is about the place of phenomenal—or felt —consciousness in the natural order. Consciousness is shown to comprise fine-grained nonconceptual contents that are “globally broadcast” to a wide range of cognitive systems for reasoning, decision making, and verbal report. Moreover, the so-called “hard” problem of consciousness results merely from the distinctive first-person concepts we can use when thinking about such contents. No special non-physical properties—no qualia—need to be introduced. The second puzzle concerns the distribution of phenomenal consciousness across the animal kingdom. Here the book shows that there is, in fact, no fact of the matter. This is because thinking about phenomenal consciousness in other creatures requires us to project our first-person concepts into the mind of another; but such projections fail to result in determinate truth-conditions when the mind of the other is significantly unlike our own. This upshot, however, doesn’t matter . It doesn’t matter for science, because no additional property enters the world as one transitions from creatures that are definitely incapable of phenomenal consciousness to those that definitely are (namely, ourselves). And on many views it doesn’t matter for ethics, either, since concern for animals can be grounded in sympathy, which requires only third-person understanding of the desires and emotions of the animal in question, rather than in first-person empathy
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