Consciousness and The Free Energy Principle: An essay review of Mark Solms book "The Hidden Spring: A Journey to the Source of Consciousness?? ? ? €
Imagine being at the Wellcome Center for Human Neuroimaging in London, where Dr. Karl Friston, a neuroscientist and physicist of extraordinary talent, holds the position of scientific director.
Dr. Friston is involved in a groundbreaking experiment that aims to generate spontaneous life-like order from chaos.
On a computer monitor, we witness clumps of randomly dancing particles self-organizing into distinct inner, outer, active, and sensory clumps.
Over time, the inner clumps develop the ability to sense their internal environment (arguably a form of proto-perception) and also interact with the outer groups (a form of unimodal proto-consciousness). These interactions form a circular causal feedback loop.
Dr. Friston refers to this spontaneous self-dividing, self-organizing mechanism with circular causality, as a Markov Blanket. It is a fundamental physical process inherent to self-organization itself, possessing an extraordinary additional property: it is one of life's most primitive homeostats.
Dr. Friston further suggests that Markov blankets have likely played a significant role in the emergence of life from the primordial soup. In fact, he proposes that the nervous system itself is a meta-Markov blanket, encompassing all the other Markov blankets that constitute it.
Dr. Friston muses that life itself likely emerged through intricate versions of this Markov blanket process.
Indeed, many aspects of what we perceive as "mental life" may have originated at the dawn of biological organization, when clumps of particles underwent division and self-organization, developing sensing abilities akin to those observed in Dr. Friston's laboratory.
In passing, Dr. Friston notes that once living cells were functioning, they would need to acquire the knowledge of organismic survival, which involves creating entropy and minimizing their free energy.
Roughly speaking, this spin-off from the second law of thermodynamics, known as entropy, measures the amount of work required to sustain an organism's life, which is the fundamental imperative of all life.
The remaining energy after accounting for entropy is an organism's free energy. Therefore, minimizing free energy is equivalent to maximizing the energy available to keep an organism alive.
By definition, life itself is the new entropic order that emerged when inanimate objects overcame the second law of thermodynamics.
From that point on, natural selection took over and equipped organisms with a purpose: to prevent them from sliding back over the thermodynamic wall back into non-life.
While Dr. Friston is a renowned neuroscientist with numerous achievements to his credit, the idea that captivated this author was presented in a 2010 paper, where Friston attempted to connect the free energy principle to Sigmund Freud's concept of psychological drives.
Throughout his career, Freud grappled with the question of how bodily needs are transformed into mental energy and how this energy then can be quantified and measured.
Although Freud never found a satisfactory method for measuring mental energy, upon reading Friston's 2010 paper, the author had an epiphany about how it might be done using Friston's free energy principle.
After all, the author reasoned, Freud's feelings and drives are merely the balanced response of nature's value system.
This "good-bad" system of evaluation, similar to the Markov blanket itself, serves as evolution's mechanism to maintain the organism's life parameters within species-specific boundaries.
Therefore, Freud's drives are essentially more refined versions of an organism's sensory and emotional thermostats-- designed specifically to keep life parameters within their species-specific limits.
With this solution in mind, Solms sought out Friston to share his epiphany.
As a result, they pooled their insights and developed a formulation that incorporates consciousness within an extended homeostatic form of the free energy principle. This principle can be applied to both physical and cognitive needs.
However, given the obvious broader implications of Friston's Markov blankets to neuroscience, the partnership naturally evolved into a deeper collaborative endeavor.
Solms quickly realized that if Friston's law could be extended to the homeostasis underlying our subjective feelings that guide decisions, it could be extended even further: it could explain consciousness as a whole.
Nevertheless, there was one obstacle before this grand partnership could take off: Friston needed to be convinced to abandon the long-held notion that the cortex is the center of consciousness.
At that time, Solms was among a select group of neuroscientists who had amassed a substantial body of theoretical evidence supporting the idea that the brainstem, rather than the cortex, is likely the proper home of consciousness.
Leading this brainstem-centered revolution was Professor Antonio Damasio.
His acclaimed book, "When Sense Comes to Mind," had laid the foundation for a transformative shift in neuroscience.
Within the brainstem, the reticular activating system (RAS) initiates consciousness by transmitting inputs to the cortex. Conversely, another brainstem component, the periaqueductal gray (PAG), receives all cortical outputs.
Among the revolutionaries, Solms was prepared to risk his reputation by asserting that the RAS and the PAG collectively represent the beginning and the end of all conscious activity within the brain.
Furthermore, the brainstem-centered theory addressed many of the outstanding questions related to the location, origin, and functioning of consciousness.
Surprisingly, none of the cortical theorists had bothered to pose a fundamental question: What happens when damage occurs to these competing regions of the brain? Or, more precisely, what happens to dreams when either region is damaged?
The answer to the first question was so surprising that it is still challenging for the cortex-centered theorists to confront it: Only with damage to either the RAS or the PAG does consciousness completely disappear. In fact, the RAS functions like an on/off switch for consciousness.
On the other hand, when the cortex itself is damaged (even to the extent of being completely removed from the brain), affective consciousness remains entirely intact.
As for dreams, the results are more intricate but still support the notion that the brainstem rather than the cortex is the seat of consciousness.
Furthermore, if this weren't sufficient evidence to convince anyone that the brainstem is the seat of consciousness rather than the cortex, there's more: All feelings are generated entirely from the brainstem (undoubtedly it seems, as an evolutionary improvement to the primitive sensing abilities self-organized by Friston's hypothesized primordial Markov blanket).
Additionally, it has been a well-established fact that the brainstem rather than the cortex is the source of most of the neurotransmitters that have proven highly effective in alleviating contemporary society's psychological problems.
Thus, while the evidence is not yet conclusive, it is robust and consistently points to the fact that the brainstem rather than the cortex is the home of consciousness.
Whether or not Friston changed his mind, the author was confident that he was on the right track and was likely onto something significant.
For not only was all the evidence converging towards Freud's idea that mental energy can be expressed through homeostasis, free energy minimization, information theory, and Dr. Friston's Markov blankets, but also, it became increasingly evident that the essence of homeostasis in living organisms directly points to feelings and affects as measures of nature's own value system.
Once we abandon the cortical fallacy, we open up a whole new range of theoretical possibilities, and the implications of this convergence are enormous:
If we take Dr. Friston's Markov blanket idea to its logical conclusion, it becomes reasonable to conjecture that perhaps consciousness itself is a much older and more primitive evolutionary development than the later, more modern one hypothesized to emanate from the cortex.
In fact, it is likely that consciousness is as old and as fundamental as metabolism itself.
One thing that self-organization through a Markov blanket suggests is that from the very beginning of life, evolution had already equipped living organisms with the precursors of not only metabolism and embodied life, but also with sensing abilities that are easily seen as the precursors to perception, selfhood, and consciousness.
By the 1860s when Darwin's insights began to permeate the scientific culture, we now know that natural selection had already equipped biological organisms with the intrinsic purpose and aim of survival and reproduction-- both of which are clear manifestations of self-organization.
It also appears clear that homeostasis, affective feelings, perception, and a sense of self may have evolved together at the beginning of organic life, rather than much later as part of the neocortex.
In the end, what we truly need to understand is how nature managed to combine these components into the unified whole we now call a self conscious mind.
The author, following in Friston's footsteps, posits that the connective tissue between the physical and cognitive components that gave rise to the self-conscious mind is "information" in its broader, more general form of entropy.
In this form, information can be applied to both physical and non-physical phenomena, such as affective states, and then measured as probability distributions across various mental states, including psychological decision-making processes.
In this case the laws of thermodynamics can therefore be seen as a special case of the deeper laws of probability.
Therefore, active information and probability theory can serve as the bridge that connects the physical and cognitive realms.
This is important because thermodynamic laws apply only to material (tangible, visible) systems, such as brains, while information laws and probabilities apply also to immaterial (intangible, invisible) systems, such as minds.
Taking this all into account, the author provides a series of hints that suggest how this connection might be established:
When Friston examined the functional status of the internal subsystem of his simulated organism, he found that the internal dynamics that predict an external event appear to emerge in their fluctuations before the event itself - as if internal events were modeling external events.
As noted earlier, the subsystems best predicted were the ones furthest away from the internal states.
This of course illustrates how internal states "infer" or "register" distant events in a way that is similar to perception. This inference ability turns out to be the most significant property of such systems.
That the Markoff blanket and its internal states have the capacity to represent hidden external states probabilistically, so that the system can then also infer the hidden causes of its own sensory states is a function deeply akin to perception.
This capacity, in turn, enables it to act purposefully upon its external environment on the basis of its internal state - which actions are now akin to motor activity.
In this way, the system maintains and renews itself in the face of external perturbations. In fact it is at this point that it can now be said to have a sense of itself.
Thus, merely being a self-organizing system is sufficient to confer a purpose on it and on each of its parts, and that is the function of the active states of the Markov blanket: they manipulate the environment in order to maintain the integrity of the system.
Which means that, along with an enclosed self, a subjective point of view, a goal, and the capacity both to sense and act, the mere fact of a Markoff blanket brings about something akin to agency.
Thus, any biological self-organizing systems must infer the hidden causes of their sensory states even though there is yet no such thing as consciousness.
Why must they do so? Because if they do not, they cease to exist.
Living organisms are obliged to model causal dependencies in their environment, so that their actions in the world ensure their survival.
They simply do not have the option not to model their environment. Indeed, this is what it means for biological self-organizing systems to be homeostatic.
They must test their models in the world, and if the world does not return the answers they expect, they must urgently do something differently or they will die.
The question that a self-organizing system is always asking itself is simply this: will I survive if I do that? The more uncertain the answer, the worst for the system.
This is a brave, complex, interesting and possibly paradigm-shifting addition to neuroscience. Ten stars
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