Why isn't there just one quale? (qualia)

Question

As far as I know, the hard problem of consciousness is focused on how the physical and mental states relate. However I haven't been able to find any attempts to answer the question of why the "physical" phenomena such as transfers of information create qualia of seemingly fundamentally different qualities.

I have thought about this question while studying action potential and realizing the electrical signal neurons send are in principle the same whether they come from cells detecting heat, pain or visual information even though the resulting qualia are incomparable.

In other words, are there any theories explaining how neural activity with different functions can generate different sensations?

Answer 1

Perhaps you will find this answer relevant The Origin of Thought

When we look at the connectomes of simple organisms, we see various 'input channels'. Neurons that specialise in tasks like self-other determination. We can extrapolate that 'primitive' into specialised regions for touch, and proprioception.

When we look at convolutional neural networks, we see how a series of specialised subroutines can operate together: edge detection, 3D shape identification, movement identification etc. Leading to reactions (see the book Thinking Fast And Slow). And building a picture - this relates to the Global Workspace Theory of why we have a mind and unified awareness.

If you look at split-brain patients, where the hemispheres were separated as a medical procedure, it was revealed one hemisphere is focused on integrating information about the self & the body, the other on building a picture of the world. Information from a given channel can contribute to both - eg our sense of balance is primarily visual, secondarily from our ear canal, and also fed information by proprioception - we use these channels in a dynamic way, and we can stimulate better awareness through learning, as people undergoing physiotherapy do (consider how reduction in working memory with ageing makes falls more likely - working memory limits the 'global workspace' size).

The split-brain case illustrates the multi-agent nature of our brains, and how we don't directly experience sensations, but constantly process them and integrate them into a picture that also involves our intentions and purposes - see Donald Hoffman on why we can't rely on evolution to show us reality. Also Anil Seth on why our 'reality' is better described as a useful hallucination.

In your example, we can picture the channels of say heat and pain, as rooted in the role of individual specialised neurons in the early connectome, successively hijacked by additional purposes. Pain is highly subjective, with heat-blistering strongly dependent on attention, and inducible by touch alone under hypnosis. Critical injuries like being shot often don't trigger pain initially, and we consciously trigger the adrenalin to get out of danger - or trigger instinctive responses and go into shock, which may be helpful, or may kill a person. Pain is not best described as a 'sensory primitive', because a lot of processing is done around identifying threats & dangers, with inputs from multiple channels. But there are action-potential thresholds being crossed by specific neurons, which feed into specialised networks linked to particular purposes, and feed into brain regions which abstract useful information into layers of convolutional neural networks, which build a picture, and tag for urgent responses like reflexes, or adrenalin response/fight or flight.

Answer 2

First of all, qualia are inaccessible to science; they are not verifiable by any independent observer. Yet they are the foundational experiences which any scientific observer relies on in order to observe anything. They thus represent one of life's profoundest mysteries.

They appear, subjectively, to accompany certain kinds of information generated by brain activity. Indeed, the way in which their distinctive qualities are experienced is a perfect match to the way in which those pieces of information are distinguished. You ask why this is? There are two aspects to that:

• If they did not reflect every nuance of the information of which we are conscious, they would be useless. For example I have very poor musical pitch, consequently so many aspects of my musical qualia appear subtly indistinguishable that I had to give up learning the violin. So the property you ask about is simply an imperative.
• Digging any deeper into a profound mystery requires some other aspect of that mystery to relate to. Suitable aspects appear sadly lacking. The ultimate answer, as to how the trick is pulled, remains a part of that mystery.

Answer 3

"As far as I know, the hard problem of consciousness is focused on how the physical and mental states relate."

It is necessary to make the distinction between qualia and mental states. A quale is the quality of our subjective experience. Mental states are best understood as the informational content of our mind. Our mental states are in principle open to the empirical investigation typical of the sciences and as long as they keep trying hard, cognitive scientists should be able to improve the science of our mental states, at least up to a point. Qualia seem in principle inaccessible to science. This is somewhat paradoxical since there is nothing we know better than our qualia. I would even say myself that this is the only things we actually know. Everything else can only be believed or disbelieved. However, while seemingly paradoxical, the situation vis à vis qualia can be compared to the fundamental constituants of reality we in principle expect exist. We haven't found these constituants yet, or if we did, we don't know that we did.

But suppose that we did, then how will we explain the nature of these fundamental constituants? The answer is that we will be unable to. You can only explain something in terms of something else: elements in terms of atoms, atoms in terms of elementary particles etc. Once you get to the ultimate ontological furniture of reality, we will have nothing else with which to explain them. We will just have to take them for granted.

Our qualia may be in a similar kind of epistemological trap. We just have to take them for granted.

Answer 4

This blurry picture you have addressed is related to a commonly misunderstood or overlooked concept of emergent phenomena.

It seems to me that neural activities -all those action potentials, local field potentials, neurotransmitter release patterns etc- are simply correlated with qualia and are not the cause of it per se, their orchestrated action is what leads to qualia. Quale is irreducible and emergent, i.e. cannot be solely explained with concepts that form the basis of it. It is much like the concept of life itself. For example, a neuron has as much qualia as a protein by itself has life, I hope that makes the argument clear.

The problem with observing emergent phenomena is that the parts that are composed to form a novel property does not reflect the emergent property per se, that is why you cannot observe how a change in the transfer of information leads to a qualitative change in qualia. This also is the case with life, we cannot just throw in a bunch of biomolecules and expect life to emerge. The idea behind this is that configuration itself is as important as parts themselves.

There also is the possibility that we may lack the science or technology at the moment. If we dissect the compositions of cognition to a certain degree in the future, we may in turn find out a way to rearrange or configure fundamental parts to form qualia. Figuratively, we may even be able to transfer qualia, or make access of it, between each other.

The unique problem of qualia is that we try to liken to with conceptually simpler emergent phenomena, as we naturally attach it a special degree of uncertainty because of the explanatory gap. We have to accept qualia as is, just as we have to accept "life" as is. There also is not a physical description of "life" itself, based on physical laws. The information that exists about "life" is limited to mechanistic explanations.

Consider the following example: A flock of birds might have a quale, but we cannot know, as we cannot have direct access to it just like we don't have access to each other's qualia.

These claims are not my own but are derived from the collection of ideas by Gestalt psychology, holism, complex & dynamic systems theory, AI, cellular automata and more importantly Minsky's Society of Mind thesis.