Chapter 3. Perceptions as Qualia: Bits, Bytes, and Packets
The Tripartite Organismic Stimulus-Response Cortical Augmentation model (TOSCAM) consists of four components so far: the human body; the subconscious; the conscious mind; and as-yet undefined stimuli, which I temporarily referred to as qualia. This post will explore this last component in more detail.
I did some more reading and discovered that perception is conceivably more complex than simply seeing or hearing something. Philosophers have constructed many theories to try and understand what we see, etc., including the physicalist model, which (greatly simplified) proposes that nothing is going on in our mind. A signal, like the light spectrum from an object we are viewing, is processed into a series of neurons firing and sending a representation of the object to our prefrontal cortex, where it is perceived as it really is. That sounds pretty straightforward, but someone pointed out the existence of hallucinations and other phenomena like phantom limbs, that aren’t representations of anything a person is experiencing. One concept that grew out of this discrepancy is Sense-Datum Theory.
Vastly oversimplified, Sense-Datum Theory proposes that sense data consist of both content and intrinsic non-representational features (e.g., blobs of paint comprising a painting). This latter signal is what is called a quale (qualia is the plural). Unfortunately a quale can’t be measured and is nothing more than a hypothetical construct, so there’s a lot of controversy associated with the idea. For example, many philosophers treat it as the sensation of perceiving (e.g., how does it feel to “see” red).
Here’s an interesting summary from the Stanford Encyclopedia of Philosophy (see note 3): “…we still seem to be left with something that we cannot explain, namely, why and how such-and-such objective, physical changes…generate so-and-so subjective feeling, or any subjective feeling at all…Some say that the explanatory gap is unbridgeable and that the proper conclusion to draw from it is that there is a corresponding gap in the world. Experiences and feelings have irreducibly subjective, non-physical qualities…There is no general agreement on how the gap is generated and what it shows.”
To muddy the water even further, here’s another interesting comment on qualia as representational: “If I feel a pain in a leg, I need not even have a leg. My pain might be a pain in a phantom limb. Facts such as these have been taken to provide further support for the contention that some sort of representational account is appropriate for qualia.”
I was going to drop the concept of qualia in my model and instead use a concrete word like sense-datum as the information-carrying medium for perception and let the philosophers argue about the details. However, I’m not going to be publishing my model in any peer-reviewed journals and I like the idea of a simple word rather than a phrase. I’ll keep qualia with the caveat that it is being used in a representational sense. I accept “some sort of representational account” as good enough for my purposes.
Without espousing Sense-Datum Theory, I am going to use the following definition of a quale (actually a sense-datum): an immediate object of perception, which is not a material object; a sense impression. I’m only using the concept, not the theory. In fact, neither quale nor sense-datum are very useful because they leave us with a vague concept of something we are aware of (perception) and not how the perception was created. How is a quale (sense-datum) created? (I’ll use the parentheses in this post only.)
Let’s think of the brain as a computer network. This is an old idea and it isn’t particularly applicable; after all, there are no main network cables within our heads but instead trillions of axons connecting every neuron to practically every other neuron with an uncountable number of intermediate neurons between them. We can get around this gross oversimplification by introducing the idea of a virtual network. For example, perceiving an object (philosophers like to use tomatoes) is the result of a complex process that turns the electrical signals from over 100 million rods and cones into an image, which is then identified, cross-correlated, and delivered to our prefrontal cortex, ready to be acted on. We may cut the tomato up or put it in the refrigerator for later use. However, those millions (who knows how many) of neurons are firing synchronously to deliver the total package of what we perceive as a “tomato.” I’m calling this organized firing of millions of neurons a virtual network (VN). A virtual network isn’t static. For example, here are some neural frequencies during different mental states.
|Beta (β)||12–35 Hz||Anxiety dominant, active, external attention, relaxed|
|Alpha (α)||8–12 Hz||Very relaxed, passive attention|
|Theta (θ)||4–8 Hz||Deeply relaxed, inward focused|
|Delta (δ)||0.5–4 Hz||Sleep|
These data suggest that any given VN (say, that associated with looking at a tomato) is at risk of being deleted as often as 35 times per second, and at best lasts a couple of seconds. Obviously, we can hold a thought or perception longer than this; what this implies is that any specific quale (sense-datum) must be refreshed or updated continuously or it will be replaced by something new (perhaps a carrot lying next to the tomato).
To complete the network analogue for the TOSCA model, we need to define qualia in more detail. The digital model of bits (binary device that can be on or off, 0 or 1, etc.) seems appropriate to describe the smallest unit of information transfer among neurons, which are either on or off. Some arbitrary number of neurons firing in unison as part of generating a quale (sense-datum) is somewhat analogous to a byte for the TOSCA model. In most computer applications, a byte consists of eight bits. This is the smallest unit of storage in computer memory, but we don’t have that restriction in the brain. Nevertheless, it is a useful concept because a byte is not sufficiently large to generate the perception of a tomato. For example, a few dozen neurons (bits) could form a byte that contains information only about the color of the tomato, and other bytes would encode other characteristics (e.g., location in space, roundness, softness).
To assemble a quale (sense-datum) for the perception of an object, thought, emotion, etc, we need to organize all those bytes coming in from millions of neurons over the VN. This can be done using the concept of a packet borrowed from digital networking. A packet contains both data and information about how it should be decoded, a perfect idea for the model. For example, groups of bytes can be virtually organized into packets that contain shape information, etc, and telling the receiving part of the brain (e.g., the prefrontal cortex) which ones go together. No one has a clue how this is done. It is an abstract concept even in brain research. We only need the concept to continue; and with the idea of multiple packets arriving from different brain areas with information about what they contain, a quale (sense-datum) can be perceived.
This has been a moderately technical post, but it was necessary to have a complete concept for the TOSCA process before applying it to real-world examples. The next post will focus on visual perception and how it can be studied, using introspection to examine and control qualia, or sense-data.
Qualia. Stanford Encyclopedia of Philosophy. First published Wed Aug 20,
Huemer, Michael, “Sense-Data”, The Stanford Encyclopedia of Philosophy (Spring 2019 Edition), Edward N. Zalta (ed.).