It’s a truism that everyone has a different idea of what they’re talking about when they refer to “consciousness”, and so there are very many different theories of consciousness. Psychule Theory proposes that (almost) all of these theories have the same fundamental basis, namely, pattern recognition (well-defined, see below). Thus, Psychule Theory is a “minimal unifying model” as described by Wanja Wiese. The term “psychule” is meant to indicate the minimal unit of consciousness, just as a molecule is the minimal unit of a substance.

Psychule Theory claims that consciousness can be entirely explained using only what we know about physics, but that explanation also requires an understanding of properties which are not physically measurable but nevertheless derive from physics. These properties are goals, information, and communication. This essay will provide a brief description of the natural physical derivation of these properties. It will then describe the impetus and requirements for the instantiation of “pattern recognition” as a base unit of consciousness, and something of the natural history of complexification by reiteration of this base unit up to a general structure applicable to the human brain. The essay will then show how this theory applies to and/or explains some other major theories of consciousness, and finally will touch on more exotic examples of consciousness, like AI.

Measurement as pattern detection

When physical entities interact they follow specific patterns which we call the laws of physics. Thus every physical interaction results in a pattern realization, the pattern being the combination of (measurable) prior states plus the (measurable) resulting states. The pattern is “real” because the resulting states are in fact measurable.

Goals

A system can be said to have a goal, by definition here, if

1. there is a specific (measurable) state of the world called the goal state,

2. the system tends to select mechanisms which can measure (detect) the current state of the world,

3. the system tends to select mechanisms which can move the world toward the goal state, and

4. the system tends to coordinate the detection of a specific current state with a mechanism which moves the world toward the goal state.

Another way to say this is that the system tends to generate mechanisms which detect a discrepancy from the goal state and respond with mechanisms which move the world toward the goal state. The first such system we will be concerned with is the one we call Nature, the system which is responsible for Life.

Information

Because physical interactions follow laws (patterns), any given physical state, detectable by measurement, is the result of prior interactions of entities in different (from the current) measurable states. Every physical interaction we care about involves a physical change. Because only certain prior (measurable) states could possibly lead to the current (measurable) state, measuring a current state potentially provides us with indications of what the prior states were. These indications can be thought of as counterfactuals with associated probabilities. Eg., if we measure X at time 1, there is a probability that at time 0 we would have measured Y. We call this property, i.e., the property of indications resulting from measurements, mutual information. We say X shares mutual information with Y. This property becomes an affordance for a system with one or more goals.

Communication

As stated above, a system with a goal can further that goal by selecting and coordinating two mechanisms, a detection mechanism and a response mechanism. In some cases the response can be directly linked to the detection mechanism. A classic example of this is the Watt governor (google it) or analog thermostat. In other cases, the response mechanism will necessarily be at some distance from the detection mechanism.  A classic example would be in bacterial chemotaxis, wherein a cell surface receptor must detect a specific molecule (sugar?), but that detection has to be conveyed to a mechanism on the other side of the cell, the flagellum. In this case the detection mechanism can generate a signal, such as a specific molecule. As described above, this signal molecule will bear mutual information with respect to the pattern detected. This signal can then be transported to the response mechanism, where it can be detected and responded to. Note that the physical structure of this signal is arbitrary to the extent that it can be produced by a detection mechanism and transported to a response mechanism. The key is that the mutual information with respect to the detected pattern is conveyed to the appropriate response mechanism. This combination of pattern detection mechanism, signal medium, and response mechanism is what I call pattern recognition and designate a specific example as the psychule, the minimal unit of consciousness.

Minimal Unifying Model

In a recent paper, Wanja Wiese identified the need for a Minimal Unifying Model (MUM) (https://academic.oup.com/nc/article/2020/1/niaa013/5870169). Psychule Theory purports  to provide such a model, designating the psychule as the minimal unit of consciousness. As explained elsewhere, several current theories can be unified by explaining how they are based on this form of pattern recognition (psychules). But here I will describe a very abbreviated natural history leading from the simplest psychules to the complex varieties in the current human brain.

Evolution

The first psychules were probably associated with cell-surface receptors in single cell organisms like the chemotaxis receptor mentioned above. Another example of early psychules involves cells communicating with each other. Note there are two kinds of such communication to consider: loud (e.g. releasing a molecule outside the cell which goes to multiple targets) and quiet (releasing molecules directly into single targets via a gap junction).

Next is the development of cells whose sole general purpose is to perform these detections/communications: aka neurons. Via neurons, communication can go to very specific distant cells. And once you have neurons, you can develop very sophisticated communications with other neurons, giving new, useful, and complex information processing (Neural nets) all based on psychule-type pattern recognition.

Now I will describe two structures which I think are significant for how consciousness functions in advanced (human) brains. The first is a general purpose pattern recognizer. In her book “Beyond Concepts”, Ruth Millikan introduces the idea of Unicepts and Unitrackers. In short, Unitrackers are general purpose pattern recognition mechanisms. They learn to track a single concept (thus unicept), although the exact pattern they track is plastic in that it can shift or even disappear. (See here for an online description: https://philosophyofbrains.com/2025/09/15/ruth-millikan-unicepts.aspx) I currently postulate that the role of unitracker in the human cortex is played by the L4 pyramidal cells and the L2,3 cells associated with each.

The second significant structure is the semantic pointer which is described by Chris Eliasmith’s Semantic Pointer Architecture (SPA). A semantic pointer is essentially a convolutional neural network. This is the kind of network where you can famously perform operations like “King – Man + Woman” and the network would output “Queen”. The gist of the semantic pointer is that you can apply multiple input vectors to a network from individual sources, then perform operations on those vectors individually or as a group, and then input a query which will return one of, or a set of, those input vectors. The outputs are “semantic pointers” in that they can activate the sources of the appropriate inputs.

So how do these structures apply to psychules? Obviously the unitrackers are acting as pattern detectors, but from where are the patterns that they detect coming? In some cases they’re coming directly from other unitrackers (L4->L2,3 —>L4), but in other cases they’re coming from intermediate networks acting as semantic pointers, such as an area of the thalamus. A semantic pointer network (eg.  thalamus) would act as a viewing screen or a broadcasting workspace for an audience of unitrackers. Those unitrackers which are activated by this screen/workspace could then generate a combination of responses could include feedforward to the next set of unitrackers in a hierarchy, feedback to the screen or prior unitrackers, and some additional action(s) for control purposes (muscular, endocrine, attention, etc.)

Consciousness

How does Psychule Theory explain consciousness? To my understanding there are three main categories of consciousness theories: top down, bottom up, and out of nowhere. Top down theories essentially start with the most complicated form of consciousness, human, and try explain the phenomena they find. The obvious examples are Global Neuronal Workspace, Predictive Processing, Attention Schema. Each of these can be explained by layers of neural networks, some of which constitute an audience of unitrackers while others constitute semantic pointers. The semantic pointers are “workspaces” which get inputs from lower unitrackers and broadcast to an audience of higher unitrackers. The outputs from unitrackers include feedforward  as well as feedback (prediction) to lower layers. And it’s possible to control attention by activating some unitrackers from the top (as opposed to bottom up) and suppressing others, thus altering their reactivity patterns.

The major bottom up theory is Integrated Information Theory (IIT). Psychule Theory (also a bottom up theory) largely agrees with IIT, but without the more mind-bending parts. As far as psychule theory is concerned, IIT’s value of Phi is a perfectly good way to identify an instance of a given pattern recognition and quantify the mutual information that detection has with respect to a pattern detected. Nevertheless, I think recent work under the title of Integrated Information Decomposition does a better job of that.

Another type of bottom up-ish theories are those which emphasize “feelings” and “valence”. Bottom up-*ish* because they actually start in the middle, but then aim up. The prime example is Mark Solm’s theory, and the primary indicator is the example of anencephalic patients who essentially lack a cerebral cortex and yet show indications of consciousness. Psychule theory describes the responsible psychules as “loud” because the pattern detections happen in the lower or mid brain but tend to generate their effect via systemic signals like neuroregulators, hormones, etc.

“What it’s like”

Finally, I will try to address the proposition that something is conscious if there it is something it is like to be that thing. Psychule theory says that an entity’s Umwelt is the set of patterns (and associated responses) that entity can recognize. To say one pattern is “like” another requires a capability of putting two different patterns into a context and then performing an action on that context. As explained above, this is an advanced capability which can be accomplished with semantic pointers. As such, any theory which requires this capability, i.e., explaining “what it’s like” falls into the top-down category of theories.

That’s the short form of Psychule Theory. Some day I may generate a longer form. Hopefully.