Thursday, September 26, 2019

The quality of qualia is not feigned


One concept that keeps cropping up in philosophical discussions of consciousness is qualia. This term was coined by philosphers to denote the subjective quality of a percept. The classical example is the subjective experience I have of red or orange, feeling pain, or the taste of this apple or the smell of this rose,  or my immersive experience of a piece of music.

Do I experience blue or green the same as you? Particularly when you consider that some languages don't even have separate words for blue and green.

Even when you and I look at exactly the same shades of red and blue as we watch the sun set over the sea, do we subjectively perceive it the same way? How do I know that the sensations I get for red aren't more like the ones you get for blue?

How can I describe these reds and blues to a blind person? Or this symphony to a deaf person?

There is a phenomenon called synaesthesia where people experience qualia from one sense when presented with something in another sense, or even associated with abstract ideas like numbers or letters. For examples sounds may elicit distinct tastes or colours.

Someone who for some reason lacks a particular sense will often have some sort of synaethesic effect.  Generally the parts of the brain that process that sense will be commandeered for other purposes, and will in particular provide additional real estate to enhance the capabiilities of senses processed in adjacent areas.

We live in an immersive environment where all our internal and external sensory organs are continuously being stimulated to one degree or another and perceived through the central nervous system, which in turn controls every muscle in the body and in turn affects our internal and external environments. This is what we mean by sentience.

Living and learning in this sensorimotor experiential world requires us to make connections between the signals that relate to different parts of our body and our world.  The whole body is reflected in, or rather projected to/from, sensory and motor homunculus  regions of the outer layers of your brain (cortex) on top of your head, ear to ear. The association cortices form associations within and between modalities, in particular above and between the corresponding homuncular area (central). The visual input projects to the back of the head (occiptal) and there are areas for auditory, vocal and speech input/output on the sides of the head (temporal). All these areas of the cortex transmit information to the parahippocampal gyrus which allows learning of associations between the various internal and external parts of the body as well as  the experienced world.

When we experience an event, for example clap our hands, the neurons associated with the motor neurons and touch and pain sensors of the hands,and the accompanying auditory and visual experience, all show the same synchronized pattern, and this is often thought to be responsible for binding all these sensorimotor components together.  But this is backwards...

Each unique event with participating sensorimotor and cortical neurons effectively relay message back and forwards to each other producing the synchrony. Neural plasticity means that neurons that fire together get the connections between them strengthened which means they are more likely to fire when the other neurons they are associated with do, and thus predict or preempt their firing, contributing as a cause of that firing.

So is my perception of red much the same as yours?

Probably yes to the extent that the reds of sunsets and traffic  lights, fires and radiators are similar.

Probably no to the extent that we live in different societies or cultures, e.g. civilized (meaning citified) vs uncivilized (meaning not based around our citified way of life). Culture, languages, morals, social expectations are all part of this external world that we experience and learn about, but it is all intertwined through our associations.

Probably no as I have a bigger, smaller or differently shaped  and configured head than you. If pathways are longer then the cycling back and forward of information takes longer so registered frequencies are slower. So we will see red differently to the extent that there is a different anatomical size and layout of our brains - remembering that brain areas grow to the extent they are used  (area grows sublinearly with frequency of use and shrinks with disuse), and new neurons are born and migrate to be incorporated where needed.

The world doesn't really look anything like what you think you see. What we think we see is an internal construction mediated by this synchrony and binding. This is especially true of colors where it seems the precise experience you have will depend on the distances between the different red, green and blue cones involved, as well as the precise arrangement of other neurons, as well as potentially the experiences you have associated with them.

Just as your computer screen takes various weightings of red, blue and green to display those flowers on the screen, so does your brain in depicting the full range of hues and tones that our sensoria can experience actually construct that corresponding internal experience, and maintain it during the sometimes conscious often unconscious scanning motions (saccades) as the small 2-3° foveal area that has high resolution and good color discrimination roves the most important features of the salient objects (esp. people) in the scene you are looking at.

This is not arbitrary, and we can actually look at these patterns using a variety of brain imaging techniques.

But qualia are not the only epiphenomenon or consciousness that we should consider - another is conscience, the idea of right or wrong, morality and ethics. But we will leave that till another blog entry.

My books

My Casindra Lost stories feature an emergent AI 'Al' and a captain who is reluctantly crewed with him on a rather long journey to another galaxy - just the two of them, and some cats... There's another one, 'Alice' that emerges more gradually in the Moraturi arc.

Casindra Lost
Kindle ebook (mobi) edition ASIN: B07ZB3VCW9 — tiny.cc/AmazonCL
Kindle paperback edition ISBN-13: 978-1696380911 justified Iowan OS
Kindle enlarged print edn ISBN-13: 978-1708810108 justified Times NR 16
Kindle large print edition ISBN-13: 978-1708299453 ragged Trebuchet 18

Moraturi Lost
Kindle ebook (mobi) edition ASIN: B0834Z8PP8 – tiny.cc/AmazonML
Kindle paperback edition ISBN-13: 978-1679850080 justified Iowan OS 

Moraturi Ring
Kindle ebook (mobi) edition ASIN: B087PJY7G3 – tiny.cc/AmazonMR
Kindle paperback edition ISBN-13: 979-8640426106 justified Iowan OS 

Author/Series pages and Awards

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