Information Closure

JC - 11/18/20

In contemplation the mind is not at pause but fully active

- St. Thomas Aquinas

Outline

  • Scale problem of consciousness
  • Information Closure
  • Coarse Graining
  • NITC
  • Conscious verses Unconscious
  • Comparisons to other theories
  • Thoughts

 

Outline

  • Scale problem of consciousness
  • Information Closure
  • Coarse Graining
  • NITC
  • Conscious verses Unconscious
  • Comparisons to other theories
  • Thoughts

 

Scale Problem

  • How many neurons need to fire for there to be an associated experience?

 

 

  • Any decent theory of consciousness should be able to provide us some insight to the problem

Not sure I know the evidence. Intuitively, it seems like many neurons need to fire for conscious experience, but what about:
Local field potentials and their predictability? The Jennifer Aniston neuron? Mirror Neurons?

 

Information Closure

These two processes can interact with each other

 

$$ Y_{t+1} = f(Y_t, E_t) $$

$$ E_{t+1} = g(Y_t, E_t) $$

Y_t
E_t

$$ + \epsilon $$

$$ + \epsilon $$

  • Consider two processes: \(E_t\) and \(Y_t\)

Information Closure

Information flow, \(J_t\), is defined as the conditional mutual information between current environmental state \(E_t\) and future system state \(Y_{t+1}\) given the current system state 

Y_t
E_t
J_t(E \rightarrow Y) := I(Y_{t+1}; E_t |Y_t)

A system is informationally closed when \(J_t = 0 \)

Information Closure

J_t(E \rightarrow Y) := I(Y_{t+1}; E_t |Y_t)

J equals how much the future of the system depends on the environment MINUS how much the future of the system depends on it's own history

J_t(E \rightarrow Y) := I(Y_{t+1}; E_t) - ( I(Y_{t+1}; Y_t) - I(Y_{t+1}; Y_t|E_t))

Example Cases

  • If two processes are independent, \(J_t\) is trivially zero
  • For a non-trivial example, the environment encodes some information about the future state of the system
J_t(E \rightarrow Y) := I(Y_{t+1}; E_t) - ( I(Y_{t+1}; Y_t) - I(Y_{t+1}; Y_t|E_t))

2.1. Informational Closure Does Not Imply Causality

Two Scenarios

Modeling

  • System models environment and can predict it
    • (our brain)

 

Passive Adaptation

  • \(Y_{t+1} = f(E_t)\)
J_t(E \rightarrow Y) := I(Y_{t+1}; E_t) - ( I(Y_{t+1}; Y_t) - I(Y_{t+1}; Y_t|E_t))

3. COARSE-GRAINING IN THE NEURAL SYSTEM

Coarse-Graining

  • NTIC requires predictability in the system. Naturally benefits from coarse graining
    • I think this is in line with intuition
  • Empirically, population codes seem to be evident

4. INFORMATION CLOSURE THEORY OF CONSCIOUSNESS

ICT

Hypothesis:

A process Y is conscious if and only if it is a C-process of some process X

5 Implications

Implications

  1. Consciousness is information
  2. Consciousness is associated with physical substrates
  3. They are self-determining
    • No course graining knows anything not known to the process itself
  4. Encode environmental influence on itself
  5. Conscious processes unaware of information at smaller scales

Qualia 

  • Two ways to increase consciousness:
    • increase mutual information between current internal state and future state
    • Environment should be predictive
  • NTIC is a non-monotonic function of coarse-graining
    • ICT suggests that human consciousness occurs at a scale of coarse-graining that allows for high NTIC
  • Size of state-space of C-process associated with richness of experience
    • different physical implementations could map to the same conscious experience

5. CONSCIOUS VS. UNCONSCIOUS PROCESSING

(Un)conscious Processing

Two scenarios:

Reflexive behaviors

  • Deterministic reflexive behaviors are unconscious
  • Some pure feedforward networks can potentially be conscious

 

Adding trivial information to a process

  • adding informationally closed processes together does not effect consciousness

 

Conscious processing:

"An NTIC process can still provide environmental information without new sensory inputs"

 

Summary

  • NTIC is not a functionalist perspective
  • Evolved by chance

6. COMPARISON WITH OTHER RELEVANT THEORIES OF CONSCIOUSNESS

Other Views

Multilevel Views

  • Neurorepresentationalism (Pennartz, 2015) is a functional theory, and only considers coarse-graining in non-informationally closed systems
  • Intermediate Level Theory (Jackendoff, 1987) focuses on processing heirchary and is fundamentally different

 

IIT

  • Both are informational
  • IIT focuses on relationship between consciousness and causal interaction among elements of the system
  • Exclusion axiom: ICT allows for coexisting consciousness
  • May have different predictions of system damage

Predictive processing

  • Well integrated with Bayesian brain hypothesis
  • Fails to say why some predictions are conscious and others are not
  • Not a theory of conscious because doesn't state how inference becomes conscious
  • Can be combined with ICT
    • Calculations not conscious because they are not part of the coarse grained system

Sensorimotor Contingency

  • SMC emphasizes interaction between system and environment

 

Global Workspace Theory

  • Neural system is made up of specalized modules and a central global workspace which integrates and broadcasts information gathered from these modules
    • Only info in the global workspace reaches conscious experience
  • Doesnt give precise meaning of information broadcasting

Limitations, Future Work, and Conclusions

  • Doesn't address hard problem
    • I think out of reach for class of information theories
  • Environment not uniquely defined
  • Individuality a major problem
  • Theory should be able to use point-wise informational measures
  • Dreaming
  • No specific coarse graining functions given

Closing Thoughts

My Thoughts*

  • No learning mechanism!
    • It’s not like systems have a natural tendency to form NTIC, and it might correspond to consciousness, but what is under selective pressure is # of offspring. Therefore, no reason for NTIC unless certain things can't be done without it
  • Not clear to me why many computer programs would not be conscious? Like autocomplete or predictive models of stock market would not be approaching consciousness (not issue in IIT)
  • What about emotion?
    • Fear, love, joy, desire
  • Important to emphasize that this simply states a new axiom
  • Think dreaming is big weakness
  • How far up the chain do we take the recursion?

*I have my own theory of a connection between semantic information and conscious experience/perception

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