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2. The Evolution of Homeostats

 
 

 

“The beginnings of a differentiation of mental function can be found even in the protozoa.”
 – Wilhelm Wundt
 “It is not the strongest or the most intelligent who will survive but those who can best manage change.”
― Charles Darwin
 

 

Our behavior control systems, otherwise called our minds, consist entirely of the means to make and use homeostats.

Homeostats are not organs in the sense that livers, eyes and skins are organs. They are the chemical or electrical reactions that take place in organs. They are less what organs are, and more what organs do. In the next few pages we will discuss the bells and whistles that random mutation, because it had nothing better to do for millions of years, has added to minds, which gives ever more complex animals the flexibility to keep alive long enough to reproduce in a constantly changing world.

Once our minds only consisted of the reflexive homeostats that nourish our cells, beat our hearts or blink our eyelids, now evolution has added another kind: learned homeostats; they love our families, read books and quest after scientific explanations. Life threatening extremes can now trigger either kind to oppose and correct any imbalance. Inborn, hardwired, reflexive, ones fix on-board problems. Insulin counters high blood sugar; each breath fixes a lack of oxygen. They are routine problems with evolved solutions. In addition, learning animals like us have evolved a mechanism for learning ad hoc homeostats that also maintain a constant steady state of health. Learned homeostats deal with the surprising and unexpected. Over a lifetime, our brains make millions of learned homeostats to deal with situations that evolution has not anticipated, like the danger of atomic radiation or driving a school bus in a snowstorm. Unlike reflexive homeostats, learned homeostats can be tailor-made on the spot and quickly overwritten as needed to deal with evolving threats and opportunities.  They keep your blood sugar constant by getting you to plant zucchini or swindle a bank rather than adjusting your insulin. They control our bargain with the rest of the world by eyeballing the neighborhood beyond our skins and, like all homeostats, mobilize actions intended to keep our physical condition balanced and our genes safe.

If you were to design a self-sustaining organism or machine from scratch, you would quickly run into the energy problem. Using a reflexive homeostat, one-celled animals have evolved to ingest fuel. The original probably looked like the reflexive, cell wall found in modern protozoa. It is able to recognized food grade particles that bump against it and act to absorb them. That kind of life sustains itself to reproduce because DNA grows the ability to recognize food by its molecular shape that acts as a key to open the cell wall. It needs no nerves or brain to carry or store that information. Ingesting everything would not work nearly as well as identifying the fuel.

Artificial intelligence (AI) experts currently use a similar reflex like algorithm to program robots. They aim to program the robot to identify specific situations and act accordingly. The coding, like the automatic reflexes it mimics, recognizes one situation and responds with one action, which forces programmers to anticipate all possible situations and program all appropriate responses. Now that is a big job. We learning animals use another somewhat more adaptable algorithm that recognizes general situations and uses feedback to control the response. It allows us to recognize variations in situations and modify our responses to suit the current instance. As was said in the first chapter, evaluative organs function as executive consciousness. Variable evaluation functions as a feedback loop that sorts the options and guides the choices necessary for a complex being to stay alive in an ever-shifting world. Pain and pleasure are the motives to keep warm, protect our modesty and eat. AI programmers will save a lot of unnecessary coding by using algorithms that incorporate the self-correcting evaluative feedback loops described in the third chapter of this work.

You can easily overlook the fact that recognition automatically includes a default evaluation; a one-celled animal does not need an evaluation when it defines the right kind of fuel by ignoring all the wrong kinds. The nutritious key opens the right lock reflexively; misevaluation would starve out the misidentifying cell walls. Cell walls control the cell’s limited behavior; they were the original minds. Even at this primitive level the basics are obvious, the cell wall cannot just recognize any bit it must be the right bit. Evolution evaluates the key as good for the purposes of survival and reproduction. Implicit evaluation works fine when only one kind of fuel works, but what if several kinds work – some better than others? Now you have choice, and evaluation becomes more important because it makes the choice. Behavior driven by evaluative control would be a great improvement. As has been explained, any random mutation in the genetic code that helped survival or reproduction was automatically included in the next and subsequent generations.

Given a few million years, evolution must have tried uncountable, ill-fated ways to make that single-cell move efficiently because locomotion would have been an evolutionary dead end without start and stop switches. The ability to flex, spin or wiggle allows the animal to pursue the useful and flee the dangerous, but moving continuously, randomly, or just not moving, would have bumped into as much danger as food. Only a basis for deciding when to start and stop would increase the chances for finding food and avoiding danger. Evolution demands an advantage before its sifting process selects for a new characteristic and the great advantage offered by movement must have developed with the ability to recognize the difference between food and danger because choice is only useful with an evaluated distinction. Recognizing one thing only requires a match. Recognizing the difference between useful and not useful requires an evaluative standard. Evolution's sifting algorithm uses life-promotion to determined when to start and stop activity. To fulfill that requirement evolution has provided an evaluative standard as a means of gauging a sensation or action’s chance of being life-promoting. It could be as simple as an acid detector that started movement and continued until the feedback indicated that the surrounding water was at a neutral pH level. If that cue prompts or stops action, it provides a basis for choosing between options.

Random mutation must have produced a few cells that generated consciousness of pleasure or pain in response to at least one stimuli. If behavior that avoided (pain) or maintained (pleasure) contact with that stimuli increased reproduction those evaluative cells would be encoded in successive genes. Random variation explains the addition of the opposite value - either pain or pleasure - adding sensitivity to more stimuli - heat, cold, hunger, sweetness, sourness - and varying the feeling intensity would evolve the kind of versatile evaluative system we now enjoy. The DNA of each species tailors the specific survival behavior by designating the evaluation of sensations with a specific degree of one of these two emotions using an automatic reflex. For example, humans have sense organs that evaluate hunger with pain and sex with pleasure. Houseflies apparently enjoy the taste of dung. We experience evaluative feelings as an executive consciousness as they enter our conscious streams coincidentally with other feelings like sight, hearing and taste. They monitor, evaluate and decide about the reality represented by the identification senses. They either control or could easily be the ebb and flow of energy that motivates us to act or not. This is no small thing; without the marvel of reflexive evaluation, we would have no preference for ice cream over poison and no way to stop ourselves from running off a cliff. Evaluation by the standard of self-sustainment or life-promotion is the genesis of intelligence.

At some later point in the evolutionary progression, recognition and action became specialized to their own organs, each needing its own kind of phenomenal sensory and muscle cells. The DNA of early simple animals must have coordinated their organs of recognition, evaluation and action by means of a primitive nervous system. It could have been as basic as recognition producing a chemical that triggered or powered locomotion. Recognizing food potential would produce one chemical to turn its locomotion on and recognizing danger would make another to turn it off. These two chemicals would have amounted to a biological evaluation of the sensations recognized as life promoting or life threatening and the means of triggering action or inaction and those three elements of recognition, evaluation and action must exist together in any effective optional behavioral system.

Because we share so much of our DNA with the other learning animals, their sense organs, nerves and brains look much like ours and so it seems reasonable to assume that theirs, although perhaps in some ways less evolved, work mostly the same way ours do. We cannot know that because each of us only has access to our own mind, and while we can describe how ours work to each other, the other animals aren't talking.

The Hippocratic and Epicurean mind theories agree that brains store life-promoting information, but disagree about which organs gather and use it. The Hippocratic model assumes that the brain is the mind and the five sense organs gather information so it can direct muscles. As likely as this explanation feels, we must consider other options because this one requires a, so far, impossibly complex explanation. On the other hand, the Epicurean model holds that all organs capable of awareness (including internal organs and muscles) both gather and use information; the brain just stores it. As unlikely as this model seems, it does admit to the reasonable explanation in the following chapter. It is consistent with our current understanding of biology and based on observations anyone can make.

Like our respiratory, circulatory, digestive or reproductive systems, our minds are biological systems with component organs. Obviously, the brain and nerves, but also three kinds of sense organs in combination reflexively produce our understanding and response to the world.  Of course, phenomenal sense organs are needed to distinguish what is what in the world, but unexpectedly, each muscle is a sense organ that moves instead of seeing, hearing, smelling, tasting, or touching. Just as eyes and ears remember past experience by re-visualizing or re-hearing, muscles learn by doing and remember by doing it again. Our phenomenal senses identify the parts of the world that our muscles could affect to advantage. A third kind of sense organ provides evaluation by responding to some conditions in our bodies with pleasure or pain. Those reflexes and emotions provide the standards that evaluate conditions and possible responses. Hunger for example causes pain and, just as the phenomenal senses and muscles remember how to re-enact their sensations, the memory of hunger causes pain. Just as muscles sensed and report their own conditions as tensed or relaxed our evaluative organs sense and report their conditions as various degrees of pleasure or pain. In combination, these three kinds of sense organs answer three questions. What is it? How does it affect me? What can I do to enhance or avoid that effect?

Randomly expanding the ability to recognize things and situations with additional sense organs only helped because we also had a fair number of organs able to evaluate them. As already listed, we have nutritive (nose, tongue, stomach, bladder and intestines), defensive (skin) and reproductive (nipples and genitalia) sense organs that reflexively evaluate DNA specified sensations because over the eons they have proved helpful or harmful to life-promotion. You feel pleasure from eating because your stomach, not your brain, has a reflexive homeostat generating the life-threatening feedback expressed as pain when empty and the life promoting feedback expressed as pleasure as it fills. The reflexive homeostats in skin produce the feedback pain of cold and injury and the feedback pleasure of warmth. Reflexive homeostats in the tongue produce the pleasure of sweetness and the pain of sourness. The primitive sense organs that reflexively produce the feedback pleasures and pains that mean life promotion and life threat respectively are collectively called here evaluating organs. Pleasure and pain may have always been the chemical switches that activate and stop propulsion, but now they have evolved into evaluative signals that can commute on nerves between sense organs and brain and they are variable. Emotional feedback comes in varying degrees of pleasure and pain and we can feel difference between the evaluations of gruel and cake. That feeling is consciousness. Most of us feel a greater pleasure associated with cake.

Our evaluative sense organs chiefly respond to reflexively evaluated sensations with pleasure or pain, but smiling or frowning, laughing or crying muscle responses also automtically follow according to the feeling's intensity. Other reflexive muscl responses connected to evaluative feelings include kicking, shivering, grasping, gaging and sucking, and we can only imagine that such knee-jerk reactions are useful genetic leftovers from some of the most primitive simple animal’s homeostats. Goose bumps and shivering follow along with pain from a cold sensation. The pain may well be the causal link between cold and shivering, but others must answer that question. What we can directly observe here is that while we often overlook goose bumps, we are always conscious of pain. Pleasure and pain draw a conscious response from us that can extend to and often illuminates simultaneously occurring sensations like goose bumps, frost and snow. As indicated earlier, all phenomenal perceptions are not conscious, only phenomenal perceptions timed with evaluation are conscious; all other phenomenal perceptions are irrelevant and unconsciousness. We only notice the goose bumps because we feel cold. Consciousness of our feelings evaluates phenomenal perceptions according to their potential to be life promoting.

Our brains do not understand sight; as Epicures said, our eyes are conscious of sight. They do not understand it intellectually, but rather as an energy level and pattern, that does or does not match one in memory. The same holds true for our ears, tongues and so on. Every kind of organ converts these various kinds of energy in patterns into to a single energy form - electricity. Electrical signals must be indistinguishable to the nerves and brain and so they can deal with electrical impulses from any organ using exactly the same biology. Our conscious stream has no single experiential home; we feel each element in the sense organ affected by energy changes. If you pinch your finger, only your finger hurts. Your liver is unaware of that pain, and cannot empathize. In response, your brain may reflexively freeze your muscles, but that evolutionary trick only sometimes works to stop further injury. Neither those muscles nor the brain feels pain. This makes the brain and nerves' jobs so much easier because they only need to deal with electricity not the various kinds of sensory energy (light, sound, chemicals, etc.) or concepts. Using the dedicated one-way circuits of afferent and efferent nerves allows electrical traffic to commute back and forth between every organ and the brain without interference. No separate being inside of us, the executive consciousness or brain, feels sensations; only our organs feel sensations; our conscious stream is the series of those sensations - each experienced in its own organ. The brain has no need to understand, it only needs to store the patterned charges and hold them ready to return to the sense organs. We understand the identity of things and actions in terms of their coincidental effect on feelings. For that reason, we are not aware of what we know or what it means until we remember it in each sense organ. Apples affect the mouth and stomach in a way that evaluates them as food. Houses and tents affect the skin, which evaluates them as shelter. Other people have a sexual effect on us, and we evaluate money by its ability to be converted into food, shelter or sex.  Psychologically, we are the sum total of those individually experienced conscious sensations. Often basic evaluative sensations from stomach, tongue, skin or sex organ evaluates the meaning of the eye's light sensation or ear's sound sensation.

Combining sensations of recognition with conscious evaluation can activate some of our approximately six hundred and fifty muscles to mobilize our millions of cells into a coordinated, learned action. Hippocrates had one thing correct: muscles are in one way a completely different kind of sense organ from the other two kinds and perform a different function. We are not super beings who can shoot heat rays or thunderbolts from our eyes; of all our organs that can respond to remembered instructions only our muscles can respond with world changing actions. All our action responses to pleasure or pain like speech, pulling, writing or running are muscular responses. Higher animals can make far more sophisticated responses to sweet and cold than the knee-jerk reactions of saliva, goose bumps, and shivering. We can bake more cookies or get a sweater because we can sense the cause of pleasures and pains and have learned and stored effective action responses to them in our brains.

Linked together by simultaneous experience our three types of organs provide the means to identify, evaluate, and respond to reality and its parts. Our ability to lurch onward long enough to reproduce depends on coordinating these three abilities with a brain. Neurons, millions of them, make up the cerebral cortex and in 2004, Giacomo Rizzolatti and Laila Craighero identified what they called a mirror neuron, "that fires both when an animal acts and when the animal observes the same action performed by another. Thus, the neuron "mirrors" the behavior of the other, as though the observer were itself acting.” This neural behavior could explain monkey see, monkey do imitation. Taken with Hebbian theory could also explain our fundamental ability to react to our environment. Carla Shatz explained D. O. Hebb’s theory with her catchy phrase "Cells that fire together, wire together" which, if true, would explain why learning links recognition, evaluation and action and how we react to specific sensations with appropriate coordinated actions.

The brain’s capacity to learn and thereby preserve recognition, evaluation and action sensations in mirror neurons linked together represented significant evolutionary progress in mind development. It would allow plugging any recognition, evaluation or action into the base homeostat three-part model. Using our nervous system, the brain stores them together in a manufactured homeostat that automatically cross-references them. It only wants a matching, evaluated mirror signal to trigger an appropriate, previously-successful response to the recognition of millions of sensations with tailored muscle reactions ranging from speaking and thinking to punching and running. The next chapter is a more detailed discussion of our ability to construct a life-promoting homeostat to deal with an evolutionarily unanticipated opportunity or threat.

 

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