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| title | chunk | source | category | tags | date_saved | instance |
|---|---|---|---|---|---|---|
| Consciousness | 10/18 | https://en.wikipedia.org/wiki/Consciousness | reference | science, encyclopedia | 2026-05-05T13:40:02.432894+00:00 | kb-cron |
=== Academic definitions of consciousness ===
Academic definitions can be found in the work of Tononi's integrated information theory, Craig MacKenzie, and Cleeremans and Jimenez - the latter being a Definition of Learning with remarkable similarity to both Tononi and MacKenzie's definitions. Both Bernard Baars and Igor Aleksander worked out the aspects necessary for consciousness. Tononi's definition is as follows:
according to Integrated information theory (IIT), consciousness requires a grouping of elements within a system that have physical cause-effect power upon one another. This in turn implies that only reentrant architecture consisting of feedback loops, whether neural or computational, will realize consciousness.
McKenzie's definition begins:
Consciousness is the capacity to generate desires and decisions about perceived or imagined realities by distinguishing self from non-self through the use of perception, memory and imagination. ...
According to Axel Cleeremans and Luis Jiménez, learning is defined as: a set of phylogenetically advanced adaptation processes that critically depend on an evolved sensitivity to subjective experience so as to enable agents to afford flexible control over their actions in complex, unpredictable environments.
This definition is notable for its similarity to the global workspace theory (GWT) theatre analogy
=== Models ===
A wide range of empirical theories of consciousness have been proposed. Adrian Doerig and colleagues list 13 notable theories, while Anil Seth and Tim Bayne list 22 notable theories.
==== Global workspace theory ==== Global workspace theory (GWT) is a cognitive architecture and theory of consciousness proposed by the cognitive psychologist Bernard Baars in 1988. Baars explains the theory with the metaphor of a theater, with conscious processes represented by an illuminated stage. This theater integrates inputs from a variety of unconscious and otherwise autonomous networks in the brain and then broadcasts them to unconscious networks (represented in the metaphor by a broad, unlit "audience"). The theory has since been expanded upon by other scientists including cognitive neuroscientist Stanislas Dehaene and Lionel Naccache. See also the Dehaene–Changeux model.
==== Integrated information theory ==== Integrated information theory (IIT), pioneered by neuroscientist Giulio Tononi in 2004, postulates that consciousness resides in the information being processed and arises once the information reaches a certain level of complexity. IIT proposes a 1:1 mapping between conscious states and precise, formal mathematical descriptions of those mental states. Proponents of this model suggest that it may provide a physical grounding for consciousness in neurons, as they provide the mechanism by which information is integrated. This also relates to the "hard problem of consciousness" proposed by David Chalmers. In 2023, 124 scholars signed a letter saying that IIT gets disproportionate media attention relative to its supporting empirical evidence, and called it "pseudoscience", arguing that its core assumptions are not adequately testable. This led to academic debate, as some other researchers objected to the "pseudoscience" characterization.
==== Orchestrated objective reduction ==== Orchestrated objective reduction (Orch-OR), or the quantum theory of mind, was proposed by scientists Roger Penrose and Stuart Hameroff, and states that consciousness originates at the quantum level inside neurons. The mechanism is held to be a quantum process called objective reduction that is orchestrated by cellular structures called microtubules, which form the cytoskeleton around which the brain is built. The duo proposed that these quantum processes accounted for creativity, innovation, and problem-solving abilities. Penrose published his views in the book The Emperor's New Mind. In 2014, the discovery of quantum vibrations inside microtubules gave new life to the argument. However, scientists and philosophers have criticized Penrose's interpretation of Gödel's theorem and his conclusion that quantum phenomena play a role in human cognition.
==== Attention schema theory ==== In 2011, Michael Graziano and Kastner proposed the "attention schema" theory of awareness. Graziano went on to publish an expanded discussion of this theory in his book "Consciousness and the Social Brain". In that theory, specific cortical areas, notably in the superior temporal sulcus and the temporo-parietal junction, are used to build the construct of awareness and attribute it to other people. The same cortical machinery is also used to attribute awareness to oneself. Damage to these cortical regions can lead to deficits in consciousness such as hemispatial neglect. In the attention schema theory, the value of explaining the feature of awareness and attributing it to a person is to gain a useful predictive model of that person's attentional processing. Attention is a style of information processing in which a brain focuses its resources on a limited set of interrelated signals. Awareness, in this theory, is a useful, simplified schema that represents attentional states. To be aware of X is explained by constructing a model of one's attentional focus on X.
==== Entropic brain theory ==== The entropic brain is a theory of conscious states informed by neuroimaging research with psychedelic drugs. The theory suggests that the brain in primary states such as rapid eye movement (REM) sleep, early psychosis and under the influence of psychedelic drugs, is in a disordered state; normal waking consciousness constrains some of this freedom and makes possible metacognitive functions such as internal self-administered reality testing and self-awareness. Criticism has included questioning whether the theory has been adequately tested.
==== Projective consciousness model ==== In 2017, work by David Rudrauf and colleagues, including Karl Friston, applied the active inference paradigm to consciousness, leading to the projective consciousness model (PCM), a model of how sensory data is integrated with priors in a process of projective transformation. The authors argue that, while their model identifies a key relationship between computation and phenomenology, it does not completely solve the hard problem of consciousness or completely close the explanatory gap.