Neurophilosophical solution
to the hard problem of consciousness

UMK - logo

    Włodzisław Duch  

duch1

Computational Intelligence Laboratory,
Department of Informatics,
Nicolaus Copernicus University,

Grudziądzka 5, 87-100 Toruń, Poland.

WWW: https://www.is.umk.pl/~duch


  1. Meaning and understanding


  2. Hard problem and its solutions


  3. Platonic mental spaces


  4. Consciousness and qualia


  5. Conclusions and predictions





1. Meaning and understanding

Add speech recognition;
add natural language dialog system;
add emotional expresions;
add body and non-verbal communication;
add human-like computing power ...

In the limit: real mind, conscious artilect or smart calculating device?

How to understand the mind? How to define the mind?

Philosophy: focus on intellectual understanding, truth
Frege, Tarski, Bunge, Castaneda, Davidson, Dummett
Cf. K. Popper: propositions are the bearers of truth; evaluation of propositions should be at the center of our epistemic focus (Objective Knowledge. OUP 1972).

Cognitive science: embodied cognition, non-Cartesian Cognitive Science (Merleau-Ponty, Dreyfus, Varela, Lakoff, Johnson).
Truth of dancing, music, art, poetry and truth of logical reasoning.
Understanding with the whole brain, not just using the left temporal lobe !
Formalistic, Confucianist science, in contrast to taoist science.
Understanding beyond reason, e.g. koans in many Zen traditions.

Meaning involves the informational content of situations.
Situation theory and situation semantics (Barwise, Perry 1983).
Relational nature of information.

Embodied cognition: behavior (including human decisions) may only partially be explained using symbolic models.

Mind is what the brain does - neurophilosophical definition.
Churchland P.S: Neurophilosophy (MIT Press, 1986)
The Mind-Brain Continuum, ed. by Llinas R. R. & Churchland P.S. (MIT Press, 1996).
Churchland Paul: Engine of reason (MIT Press, 1995)

Mind is an ego-centric, subjective simulation model of the world.
Ego-centric implies intensional, a "meaning machine" (W. Freeman)
Precise definition that will cover all uses of the word "mind" is impossible.

Conceptual problems with neurophilosophy.
The Central Paradox of Cognition: how can the structure and meaning, expressed in symbols and ideas at the mental level result from numerical processing at the brain level?
What has the brain or a model to do with my experience?

Some concepts that were/are dificult to understand


History of science: conceptual understanding is the most important motivation.

Mind science: still pre-Newton stage?
Copernicus did not realized what riches he had (Kelper).
Neither did Kepler, nor do we.
The problem comes from asking wrong question because of wrong associations.

Sketch of the argument:




Hard problem and its solutions

Hard problem of consciousness: qualitative character of phenomenal experience (PE).
Why are we not zombies?
Is there a function of phenomenal experience?
How to program something that does not make a difference?

Many assumptions may be wrong, eg.

Old mind-body problem, new discussion from 1995, started in the Journal of Consciousness Studies.
Chalmers D.J, The Conscious Mind: In Search of a Fundamental Theory (Oxford University Press 1996)
At least 43 reviews of the book!

Summary of the positions on the hard problem.

Theory Proponents Comments
Not a real problem Dennett, Paul Churchland Mental world reduced to dispositions, folk psychology should be eliminated;
well, my mind is for real!
Neomisterian McGinn Our minds are too simplistic for such a deep questions;
but how do we know that? Should we stop trying?
Non-reductive Spinoza, Chalmers Naturalistic dualism, physical and phenomenal aspects of information;
that's not an explanation - God wanted so?
Panpsychism Seager, Rosenberg Weak panprotopsychism: protophenomena build conscious experiences in combination with complex systems;
but why I'm not conscious in a deep sleep?
Reductionist Smart, Humprey, Searl Brain states are identical (or token-identical) with mind states, neurons have 'causal powers';
relations should be sufficient, mental level is autonomous.
Neurobiological Crick, Koch, Taylor Brain 'somehow' creates experience, more details needed;
is the solution in such details?
Quantum Stapp Quantum mechnics provides holistic view;
what can one expect from such a theory?
New physics Penrose Thinking requires non-computable processes, hence completly new physics;
good luck!



Platonic mental spaces

Levels of modeling the brain/mind:

Progress in physics: breaking the unified view of the world, introducing space and time as arena for physical events.
Platonic level: define dimensions used to analyze experience; real world (neurodynamics) is more rich.

Reality is described in infinitely dimensional space;
brain dynamics in a very large but finite dimensional space;
mind in defined in a much smaller space.
Phenomenal experience does not relate to the world, only to brain states.

Notes
Dimensions change with time, new dimensions are created.
Mind objects: primarily preprocessed sensory data, iconic representations, perception-action sequences, modeled as probabilities of recognition of particular combination of features.
Mind objects are shadows of neurodynamical states (as Plato intuitively new).
Distances between objects are proportional to their perceived similarity; they are non-symetric.

Develop mind space language/math, use it for description of psychological experiments.

Brain states and low-dimensional representations - mind states.
Moving from primary sensory areas to higher associative cortex => compresion of information.
Mental representations: memory traces allowing to find meaning is sensory data.

Example: face recognition.
Sung, K.K. and T. Poggio. Finding Human Faces with a Gaussian Mixture Distribution-based Face Model, Recent Progress in Computer Vision, LNCS Series, Springer-Verlag, 1995.

Our Feature Space Mapping neurofuzzy system is based on this inspiration.

Similar work in AI, psychology and linguistics:

Geometrical mind model, global dynamics of the brain => mind state, content of mind.

Language to speak about mind events in mind space.

Meaning: mind states are grounded in the kinestethic image and senso-motoric schemes.
First-person experience: states of mind are about something, since mind objects are monadic, non- decomposable mixtures of many features of internal representation.
Secondary mind objects - difficult to understand.


Consciousness and qualia

How does that help us to solve the hard problem of consciousness?

Davidson "anomalous monism": same mental states may correspond to different neural states at different times.
There is no relationship between the mental and (neuro)physical.
Relations (similarities and association probabilities) between mind objects must be preserved!

T. Reid (1785), and Indian philosophers 2000 years before him, distinguished clearly sensation (feeling) and perception (judgement, discrimination).
I feel a pain: looks like 'I' that has an object 'pain'.
Reification creates mystery.
It is just 'pain', sensation, a process, activity.

Red color has a particular feeling to it: sure! Real, specific brain states/mind states.
I 'have a feeling': constant non-verbal updating of mind state, feedback process and its interpretation.
Resonant states: the up-going (sensory-conceptual) and the down-going (conceptual-sensory) streams of information self-organize to form the brain/mind state.

Qualia in our PE result from the ability to discriminate between mind states.

But why do qualia exist?

Imagine a rat smelling food. In fraction of a second rat decides: eat or spit?

Rat has "a feeling" for different tastes.
If the rat could speak, what would be his comment about such episode?
Results of non-symbolic, continous taste discrimination have to be known: qualia!

Long term memory (LTM) is huge.
Small Working Memory is based on dynamical brain states (actualization of LTM potential possibilities).
Evaluation of the WM states: resonant states with senso-motoric memory patterns.

Systems capable of commenting on their own state have sophisticated WM.
Dressed WM states: different from states of the Turing machine registers.
Dressed WM states contain associations, possibilities of action, memories in one dynamical state.
Brain feedback loops match experience with action.
Such system must claim to have phenomenal experiences = real WM states.

What happend to the taste of this ice-cream?
The taste buds provide all the information
The brain processes it but the qualia are gone after a short time.
Why? WM is filled with other objects, no resonances with gustatory cortex are formed, no discrimination.
Nonverbal labeling assigns different 'feelings' to WM states.

Minimal conditions for an artilect to claim qualia:

  1. Working Memory (WM), a recurrent dynamic model of current global brain state, containing enough in-formation to re-instate the dynamical states of all the subsystems.
  2. Permanent memory for storing WM states.
  3. Ability to discriminate between continuously changing states of WM; "discrimination" implies associa-tion with different types of responses or subsequent states.
  4. Mechanism for activation of associations stored in permanent memory and updating WM states.
  5. Ability to report on the actual state of WM.
  6. Representation of 'the self', categorizing the value of different states from the point of view of the goals of the system, which are implemented as drives, giving a general orientation to the system.

Conclusions and predictions

Why do we feel the way we do?

  1. Qualia depend on cognitive mechanisms. Habituation, intensive concentration or shifting of attention should remove qualia.
    Cf. segmentation of visual stimuli from the background - qualia require correct interpretation.
  2. No interpretation, no qualia: looking without seeing.
  3. Secondary sensory cortex is responsible for interpretation; lesions will lead to change in qualia (asymbolia).
  4. Visual qualia: clear separation between higher visual areas (concepts, object recognition) and lower visual areas; activity of lower only should lead to qualia (eg. freezing V4 - no color experience).
  5. Memory is involved in cognitive interpretation: qualia altered by drugs modifying memory access.
  6. Cognitive training enhances all sensory qualia; memorization of sounds/tastes/visual objects changes qualia.
  7. New qualia should also be accesible in dreams.
  8. How does it feel to do the shoe laces?
    Episodic memory (resonant states) lead to qualia; procedural memory (maps) - no qualia.

  9. Phenomenology of pain:

    • usually unpleasant except for masochists;
    • intensive concentration on actual experience of pain changes it completely;
    • causalgia, a post-injury blazing pain, may be initiated by touch, noise or anything else;
    • placebo can be as effective as powerful anesthetics;
    • lesions to the secondary somatosensory cortex should lead to the asymbolia of pain;
    • intensity or unpleasentness of pain - proportional to the danger created by the injury;
    • without cognitive interpretation there are no pain qualia (cf. Beecher Ann. of Surgery, 1946).

  10. Unilateral neglect, body dysmorphia, phantom limbs - wrong interpretation of brain states.
    • All somatosensory sensations change after amputation due to disinhibition and corticla reorganization.
    • Phantom limbs may be controled by visual stimulation using mirrors.
    • Phantom limb illusions are easily evoked in normal subjects by correlation of tactile and visual stimuli.
  11. Synesthesia shows qualia dependence upon cognitive interpretations.
  12. Qualia should have different structural properties, matching their specific roles, cf. spatial structure of visual, tactile, temperature or pain stimuli, non-spatial structure of taste, olfaction, thoughts or imagery.
  13. Stimulation of brain structures responsible for different type of qualia should lead to actual experience only if the working memory is influenced.
  14. Feeling of disgust is invoked by vision, hearing, taste or smell; probably WM analysis by anterior insular cortex.
  15. Blindsight (covert perception):
    • visual qualia vanish since there are no discriminations;
    • serious impairment of behavioral competence;
    • information available in the brain allows for rough discriminations, but qualia should be different.
    • .....
  16. Absorption in acting or even watching a movie or a theatrical play invokes feelings and other qualia.

In discussions on consciousness good (neuro)phenomenology is missing.
Interesting parallels with Buddhist contemplative schools: "all skandhas are empty" (Heart Sutra, 350 C.E.)
Skandhas = physical body, sensations, perceptions, impulses and consciousness. pronounces.

Artificial minds of brain-like systems will claim qualia; they will be as real in artificial as they are in our mind.
We understand why qualia exist - they must exist in brain-like computing systems.
They do play functional role - like in the case of rat.
We can predict which mental events will be connected with qualia and what will be their structure - no other theory comes close.

Some notes added after discussion in Konstanz.

But what are qualia?
One more time T. Reid: pain is a process, not a thing. There is no "I' that 'has pain'. There is a process and this is what I try to explain.
But why was I born in this family? This country? This planet? Stating a question does not mean that it has sense!
All we can do is to understand why this process gives rise to experiences and what will be the structure of these experiences. Visual qualia, states of V1-V4 brain areas, are below the conceptual level, states of IT or STS. We cannot say more about them using conceptual language.

The fact that some many books have been writen on the subject, books presenting quite different points of view, does prove that most of them must be wrong. Why to accept Searl's argument based on Chinese room if the result of this argument is that no system (including our brains) understands? This is not a test! It does not help to say that we know that we understand therefore other people must understand, and this is due to mysterious causal powers of neurons. Perhaps than artificial brains will also understand due to the mysterious power of silicon chips? Is it up to our good will whom will we grant understanding?

Does than a simple robot like Edelman's Nomad, has qualia?
How about an octopus? Do they experience pain?
Again, a language trap. We can project our phenomenal experience on humans with brains similar to ours, but it even small difference in brain wiring may lead to a difference: associating pain with pleasure for example.
We should not project processes such as pain on the animals or robots if the relational structure of their brain states (hardware states) is quite different than ours.
Perhaps we should call it "octopus-sort-of pain", but even this is inappropriate.
Only in the models that are sufficiently similar to our brain to have sufficiently similar structure of their mind states can we justifiably use the same designations.
It is not enough to have a few primitive behavioral functions to talk about phenomenal experience. If we want to use words describing our experience the mind states should be similar to ours, and that means really sophisticated.

Again Kepler: we do not know what riches do we have ...














The mind-body problem is (dis)solved !