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Crick and Koch’s NCC vs Free Energy Principle

Crick and Koch’s Neural Correlates of Consciousness (NCC) and Friston’s free-energy principle and active inference, compared field by field from their entries in the Atlas.

At a glance

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The claim

In brief
Crick and Koch’s NCCThis theory proposes a scientific agenda to identify the Neural Correlate of Consciousness (NCC), defined as the minimum activities in the brain that are jointly sufficient and necessary for any specific conscious perception or subjective experience. It asserts that consciousness is entirely physical and can be fully reduced to these specific brain activities.
Free Energy PrincipleThis theory conceptualizes consciousness as a natural process arising from the minimization of 'free energy,' which is the difference between an organism's internal model (perceptual expectations) and real-time sensory inputs. Consciousness, therefore, functions as the evolved mechanism for simulating scenarios of the world and reducing prediction error to ensure survival and maintain homeostasis.
What consciousness is
Crick and Koch’s NCCConsciousness (phenomenal consciousness/qualia) is identified as the Neural Correlate of Consciousness (NCC), the precise minimum pattern of neural activity in the brain necessary and sufficient for subjective experience.
Free Energy PrincipleConsciousness is identified as a natural process of inference, specifically the internal emergent model that monitors and minimizes the free energy principle (surprise), thereby optimizing the representational capacities of physical/brain systems.

Big questions

Crick and Koch’s NCCYesIf consciousness is entirely reducible to physical organizational patterns (NCC), then non-biological systems capable of replicating those precise patterns should also become conscious, barring technological constraints.
Free Energy PrincipleYesAs a strong materialist theory, if consciousness is fully explained by computational processes of inference and representation minimization, then non-biological systems capable of executing these processes must eventually attain consciousness in principle.
Crick and Koch’s NCCNoAs a Materialist theory, consciousness is wholly dependent on the physical brain; cessation of brain function entails the end of consciousness.
Free Energy PrincipleNoConsciousness is an emergent natural process tied directly to the functional dynamics and physical substrate of the biological brain; thus, it cannot survive bodily decay.
Crick and Koch’s NCCYesIf the NCC states can be perfectly measured and replicated in a digital or artificial medium (mind uploading), the resulting system would be functionally and phenomenally identical, achieving virtual immortality in principle.
Free Energy PrincipleYesSince consciousness is understood as an emergent, formalized process of inference optimization, perfect duplication of the brain's information processing and representational dynamics in a non-biological medium should be sufficient for the continuation of the mental self.
Crick and Koch’s NCCHumanistic onlyConsistent with Materialism, consciousness is a biological product of evolution and physics, conferring no ultimate cosmic meaning or teleology beyond that which humans create for themselves.
Free Energy PrincipleHumanistic onlyThe foundational imperative of the conscious process is survival (minimizing surprise/maintaining homeostasis). The theory does not rationalize ultimate cosmic meaning or purpose, aligning with general materialist perspectives.

Nature of mind

Ontology
Crick and Koch’s NCCReductive Physicalism/Materialism. The NCC approach is considered macroscopic materialism.
Free Energy PrinciplePhysicalism; often referred to as Markovian Monism, which views mind/matter distinction as dialectical rather than ontological.
Mind and body
Crick and Koch’s NCCIdentity Theory. Mental states are wholly identical to and fully explained by the physical NCC states.
Free Energy PrincipleMonistic/Identity. The theory proposes that consciousness is the natural outcome of the physical/brain system's self-organizing processes, dissolving familiar dialectics between mind and matter.
Fundamental or emergent
Crick and Koch’s NCCEmergent
Free Energy PrincipleEmergent
Qualia
Crick and Koch’s NCCQualia (the qualitative feel of experience) are identified with the minimum neural activities (NCC) that are jointly sufficient for specific conscious perception, although the mechanism for this identity remains the central 'hard problem' challenge.
Free Energy PrincipleThe theory is highly deflationary regarding the Hard Problem, treating consciousness as a process to be understood rather than a 'thing' whose qualitative attributes need definition. Qualia, if acknowledged, would be epiphenomena or aspects of the internal generative model required for inference.

How it works

Mechanism
Crick and Koch’s NCCThe search for and definition of the Neural Correlate of Consciousness (NCC): the specific minimum neural activities necessary and sufficient for subjective experience.
Free Energy PrincipleThe Free-Energy Principle (FEP), which states that all self-organizing systems must minimize free energy (or 'surprise'), driving action and perception through active inference.
Where it is
Crick and Koch’s NCCLocalized in specific brain areas. Early candidates included the claustrum (as a 'conductor' coordinating percepts); later candidates focused on the posterior cerebral cortex (temporo-parietal-occipital hot zone).
Free Energy PrincipleLocalized in the physical brain system; cortical responses are seen as the brain’s attempt to minimize free energy.
What it does
Crick and Koch’s NCCConsciousness is directly caused by, and is identical to, the NCC activity. NCC mechanisms (spikes, flows, circuits) are seen as constitutive of phenomenal consciousness.
Free Energy PrincipleConsciousness serves an adaptive and functional role as the evolved mechanism for simulating scenarios, monitoring, and minimizing free energy to promote survival (homeostasis) and navigate the world.

Evidence and criticism

Testability
Crick and Koch’s NCCEmpirically testable. The search for the NCC is defined as a scientific program seeking testable biological bases for consciousness.
Free Energy PrincipleConceptually and empirically linked to testable models (e.g., in neurobiology and psychology) through its reliance on formalizing representational capacities of physical systems.
Tests so far
Crick and Koch’s NCCIdentifying specific clusters of neurons or brain regions (like the claustrum or posterior cortex) that are active during conscious experience.,Measuring electrophysiological activity (e.g., action potentials and neural circuits).
Free Energy PrincipleThe principles of FEP form the basis for models utilized in empirical work concerning altered states (e.g., the Entropic Brain Hypothesis under psychedelics) and related theories of perception and cognition.
Criticisms
Crick and Koch’s NCCThe primary tension is the 'explanatory gap': identifying a correlation (NCC) does not explain the identity statement of how physical activity (spikes/chemicals) literally generates phenomenal feel (qualia). The failure to identify a 'clear' NCC after decades of research is a practical limitation.
Free Energy PrincipleCriticized for being highly deflationary and difficult to reconcile with the first-person reality of phenomenal experience (the Hard Problem), viewing consciousness merely as a mathematical process or 'natural outcome.' Friston finds engaging with the philosophical premise of consciousness as a 'thing' difficult.

Sources

Key sources
Crick and Koch’s NCC
  • Towards a neurobiological theory of consciousness, F. Crick and C. Koch (1990)
  • What is the function of the claustrum?, F. Crick and C. Koch (2005)
  • The Quest for Consciousness: a Neurobiological Approach, C. Koch (2004)
Free Energy Principle
  • A theory of cortical responses, K. Friston (2005)
  • Active interference: a process theory, K. Friston et al (2017)
  • The Mathematics of Mind-Time, K. Friston (2017)

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