Piero Scaruffi(Copyright © 2006 Piero Scaruffi | Legal restrictions - Termini d'uso )
Consciousness: The Factory of Illusions
(These are excerpts from, or extensions to, the material published in my book "The Nature of Consciousness")
Science’s Last Frontier
The 20th century witnessed tremendous scientific progress in many fields. This has brought about a better understanding of the world we inhabit, of the forces that drive it, of the relationships between the human race and the rest of the universe. Scientific explanations have been provided for most of the phenomena that used to be considered divine events. We have learned how the universe was born, and how it gave rise to the galaxies and the stars and ultimately to our planet; and what life is, how it survives, reproduces and evolves; and what the structure of the brain is, and how it works.
The mystery is no longer in our surroundings: it is inside ourselves. What we still cannot explain is precisely that: "ourselves". We may have a clue to what generates reasoning, memory and learning. But we have no scientific theory for the one thing that we really know very well: our consciousness, our awareness of being us, ourselves.
No scientific theory of the universe can be said complete if it doesn't explain consciousness. We may doubt the existence of black holes, the properties of quarks and even that the Earth is round, but it is harder to doubt that we are conscious. Consciousness is actually the only thing we can be sure of: we are sure that "we" exist, and "we" doesn't mean our bodies: it means our consciousness. Everything else could be an illusion, but consciousness is what allows us to even think that everything else could be an illusion. It is the one thing that we cannot reject.
If our theory of the universe that we have does not explain consciousness, then maybe we do not have a good theory of the universe. Consciousness is a natural phenomenon. Like all natural phenomena it should be possible to find laws of nature that explain it.
Unfortunately, precisely consciousness, of all things in the universe, still eludes scientists. Physics has come a long way to explaining what matter is and how it behaves. Biology has come a long way to explain what life is and how it evolves. But no science has come even close to explaining what consciousness is, how it originates and how it works.
Neurology tells us an enormous amount about the brain, but it cannot explain how conscious experience arises from the brain’s electrochemical activity.
One wonders if there is still something about the structure of matter that we are missing.
We may have figured out the meaning of matter and the structure of life, but we were more interested in the structure of matter and the meaning of life.
What Is Consciousness?
What is consciousness? What is it to be aware? The more we think, the less we can define it. How does it happen? How does something in the brain (it is in the brain, isn't it?) lead to our emotions, feelings and thoughts? And why does it happen? Why were humans (and presumably to some extent many animals) endowed with consciousness, with the ability to know that they exist, that they live, that other people live, that they are part of this universe and that they will die? Why do we need to "think" at all?
Why doesn’t our inner life mirror faithfully, one to one, our external life? When we experience sensations related to interactions of our body with the world, our emotional life can be said to mirror the environment. But when we think, sometimes we think things that never happen and will never happen. How can consciousness be so decoupled from the environment if brain processes are tightly coupled to it? Is consciousness a form of self-maintenance the same way that the autonomic system is a form of self-maintenance of the body regardless of what happens in the environment?
Paradoxes and weird properties of consciousness abound.
Why can't I be aware of my entire being? We only have partial introspection. We have no idea of what many organs are doing in our body.
Consciousness is limited to my head. Do I need hands and feet in order to be conscious? Is consciousness only determined by what is in the head, or is it affected also by every part of the body? Am I still the same person if they cut my legs? What if they transplant my heart?
We can only be conscious of one thing at a time. There are many things that we are not conscious of. How do we select which thing we want to be conscious of?
Why can I only feel my own consciousness and not other people's consciousness? Why can't I feel other people's feelings? Why can't anybody else feel my feelings? Conscious states are fundamentally different from anything else in nature because they are "subjective" and "opaque" (I can’t feel yours). They are not equally accessible to all observers.
Consciousness is a whole, unlike the body which is made of parts, unlike everything else which can be decomposed into more and more elementary units. Conscious states cannot be reduced to constituent parts.
How did consciousness come to exist in the first place? Did it evolve from non-conscious properties? In that case, why? What purpose does it serve?
Could I be conscious of things that I am not conscious of? Am I in control of my consciousness? Is this conscious thought of mine only one of the many possible conscious thoughts that I could have now, or is it the only conscious thought that I could possibly have now? Is consciousness in control of me? This question is crucial to understanding whether there is a locus of consciousness in the brain, or whether consciousness is simply a side-effect of processes that occur in the brain.
The most frustrating property of consciousness is probably its opacity: we cannot know who and what is conscious. How widespread is consciousness? Who else is conscious besides me? Are other people conscious the same way I am? Are some people more conscious and others less conscious? Are some animals also conscious? Are all animals conscious? Are plants conscious? Can non-living matter also be conscious? Is everything conscious?
Can things inside conscious things be conscious? Are planets and galaxies conscious? Are arms and legs conscious?
What is the self? The self seems to represent a sense of unity, of spatial and time unity: "my" self groups all the feelings related to my body, and it also groups all those feelings that occurred in the past. My body changed over the years, and my brain too. All the cells of the body change within seven years. Therefore my "mind" must have changed too. But the self somehow bestows unity on that continuously changing entity. If we consider that our bodies are ultimately made of elementary particles, and that the average lifetime of most elementary particles is a fraction of a second, we can say that our bodies are continuously rebuilt every second. The matter of our bodies changes all the time. The only thing that is preserved is the pattern of matter. And even that pattern changes slowly as we age. Not even the pattern is preserved accurately. What makes us think that we are still the same person? How can I still be myself?
Laws that protect animals are not clear about "what" makes an animal worthy of protecting: killing a neighborhood cat because I don't like it is generally considered offensive, but killing a spider because I don't like it is absolutely normal. One can own a dog and file a suit against somebody who killed it, but one cannot own an ant and file a suit against somebody who stepped over it. Why slaughtering cows by the millions is a lawful practice and killing a pigeon in a square is a crime?
The USA physicist Erich Harth focused on the following properties of consciousness: "selectivity" (only a few neural processes are conscious); "exclusivity" (only one perception at the time can be conscious); "chaining" (one conscious thought leads to another one"); "unitarity" (the sense of self).
These properties of consciousness (partiality, sequentiality, irreducibility, unity, opacity, etc) set consciousness apart from any other natural phenomenon. And make it difficult, if not impossible, to study it with the traditional tools of the physical sciences.
Two Levels of Consciousness
We can take consciousness as a primitive concept (just like "time", "space" and "matter"), that we all "know" even though we cannot define it. We can define what the brain (or at least the neural system) is and what brain processes are. We can define cognition, as the set of cognitive faculties (learning, memory, language, etc), each of way is relatively easy to define.
When we refer to cognition, we are often interested in more than just the neural process underlying a cognitive faculty. We are interested in general questions such as "how can a living thing remember something" and "how can a living thing learn something". Such questions have two parts. The first part is about the mechanism that allows a piece of living matter to remember or learn something in the sense of being able to perform future actions based on it. The second part is about the awareness of remembering or learning something. The first part doesn't really require consciousness, and it may well be explained on a purely material basis. Even non-conscious things (non-living matter) may be able to remember and learn. Ultimately, the first part of the cognitive process can be summarized as: "matter modifies itself based on occurrences in the environment so that its future behavior will be different". Fascinating and intriguing, but far less mysterious than the other half of the phenomenon: "... and, in the process, it is also aware of all of this".
The mechanisms that preside over memory, learning, language and reasoning can be described in material terms. And machines have been built that mimic those processes. The other half of the problem is still as mysterious as it was centuries ago. How does a brain process give rise to the awareness that the process is going on?
It looks like by "mind" we always meant something physical, material, reducible to physical processes inside the brain, which could be reproduced in a laboratory, and possibly on beings made of a different substance. But at the same time we also meant something that today's sciences cannot replicate in a laboratory: the awareness of that physical process going on inside us.
"Mind" encompasses both the cognitive processes (of of memory and learning, language and reasoning) and the "feeling" associated with those processes: consciousness.
At closer inspection, "consciousness" is a term that encompasses a number of phenomena: thought, the self (the sense of the "I", the awareness of being), bodily sensations (such as pain and red), emotions (anger, happiness, fear, love). But not necessarily cognition (reasoning, memory, learning, etc).
There is a "narrative", "cognitive", "higher-level" consciousness, which is relatively detached from our bodily experience and which seems to rely on language, and there is an "experiential", "sensorial" consciousness, which has to do with sensations received from the senses, i.e. with our immediate bodily experience. The latter may be common to many species, while the former might be an exclusive of humans because it may require some additional level of circuitry in the brain than basic sensations or emotions.
The former is what we call "thought", including the self. The latter consist of "sensations" and "emotions".
Consciousness is the awareness of existing. Self is the awareness of lasting in space and time (of being an "I"). Sensations are bodily feelings such as pain, red, warmth. Emotions are non-bodily feelings such as anger, happiness, fear. Cognition encompasses the processes of reasoning, memory, learning, speaking, etc. Perception is the physical process of perceiving the world. Thought is the act of being conscious over an extended period of time.
The problem of phenomenal qualities has puzzled philosophers for centuries. There is no "red" around me, just particles. Where does the "red" that I see come from? That red exists in my mind, but it does not exist outside my mind. Red is in me, not in the world.
How can a reality made of atoms of finite size be generating my feeling of something as uniform and continuous as the color red?
In 1929 the USA philosopher Clarence Lewis called them "qualia" (from the Latin "quale", which is the dual of "quantum" and refers to the subjective aspect of a thing). Qualia are qualities that are subjective, directly perceived and known in an absolute way. The taste of something, the color of something, a pain or a desire are associated to qualia, to "feelings" of those things.
Qualia are subjective: I cannot be sure that another person’s "red" is identical to my red.
Qualia are known in an absolute way: in another world red could correspond to a different frequency of light, and we would have to change the branch of Physics that deals with colors, but what I see as "red" I would still see as red.
Why does Nature present itself to my senses in two contradictory ways? If I believe my immediate perceptions, there is red. If I try to make sense of my perceptions, I work out a theory of Nature according to which there is no red, but only a vast mass of floating particles.
As a matter of fact, matter is "inscrutable" to our consciousness. We would like to think that, if nothing else, we know what the world is. We may be puzzled by the nature of mind, but we do know what matter is. At closer inspection, even matter turns out to be a bit of a mystery. We cannot perceive, and therefore conceive, what matter ultimately is. Our mind presents us with a game of illusions, whereby the world is populated with objects, and objects have shapes and colors. Science, on the other hand, tells us that there are only particles and waves. We cannot perceive that ultimate reality of matter. Matter is inscrutable to us.
We know what consciousness is because we feel it. We know what matter is because we sense it. Because we can sense it, we can build scientific theories on the nature of matter. But we cannot feel it, we cannot feel what matter ultimately is. Because we can only feel it, we cannot build scientific theories on the nature of consciousness. Although we can feel it.
Feelings Are Not in the Head
The USA philosopher Michael Tye believes that our feelings are not in the head at all. Neurologists can never explain what it is like to smell or taste.
Following Jackson, Tye pictures a scientist who knows everything about a subject, but has not experienced that subject. She has lived her entire life in a black and white environment but studied all there is to know about colors. She has seen colored objects only on a black and white television set. She just has not seen them in color. But she knows what color is and what properties it obeys and so forth. Then one day she steps outside her black and white environment and experiences the colors of those objects. No matter how much she knew about colors, when she actually sees a red object, she will experience something that she had not experienced before, she will "learn" something that she did not know: the "what it is like" of seeing a color (what Tye calls the "phenomenal character" of seeing a color). There is a difference between objective knowledge of something and subjective experience of something. The latter constitutes the "phenomenal consciousness" of something.
Tye believes that phenomenal states cannot be possibly realized only by neural states (as opposed to what physicalism claims). Tye believes that mental states are symbolic representations, but he differs from Fodor in that he does not believe that the representation for a sensation involves a sentence in the language of thought. The belief of something is represented by a symbolic structure which is a sentence. The sensation of something, instead, is represented by a symbolic structure which is not a sentence. The format (the symbolic structure) of a sensory representation is instead map-like: a pattern of activation occurring in a three-dimensional array of cells each containing a symbol and to which descriptive labels are attached. The patterns are analyzed by computational routines that are capable of extracting information and then attaching the appropriate descriptive labels.
A sentence would not be enough to represent a sensation, as a sensation includes some kind of "mapping" of the domain it refers to. For example, pain is about the body, and needs a way to represent the body parts that are affected by pain. Sentences lack this map-like representational power. Tye's patterns of activation in those map-like structures are therefore representations of bodily changes that trigger some computational processing. And this is what an emotion is, according to Tye.
Tye' hypothesis is that phenomenal consciousness is not in the neurons: phenomenal consciousness is in the "representations".
Tye believes that the body is equipped (as a product of evolution) with a set of specialized sensory modules for bodily sensations (for pain, hunger, and so forth) just like the specialized sensory modules for the five senses (physically different neural regions). Each module is capable of some computation on some symbolic structure.
Additionally, Tye notes that the object of a feeling is non-conceptual. We have different feelings for different shades of red even if we don't have different concepts for those shades of red. Thus we are capable of many more feelings than concepts.
Tye concludes that "phenomenal states lie at the interface of the non-conceptual and conceptual domains", at the border between the sensory modules and the cognitive system.
Tye analyzes the "phenomenal character" ("what it is like") of an experience and its "phenomenal content" ("what is being experienced"). Tye shows that the phenomenal character of an experience is identical to its phenomenal content: the feeling of pain in a foot cannot be abstracted and remains the fact that it is pain in that foot. Tye, therefore, concludes that phenomenal aspects are a subset of the representational aspects, and not distinct from them.
Because phenomenal character (the "what it is like" feeling) is phenomenal content, experiencing "what it is like" depends on having the appropriate system of concepts: one must have the appropriate system of concepts in order to understand what it is like to experience something. I cannot know what it feels like to be a bat because I don't have the appropriate concepts to feel what a bat feels.
Appropriate concepts are "predicative" and "indexical", which can be acquired only from direct experience (past or present, respectively).
Tye does not truly solve the "explanatory gap" between phenomenal states and physical states (how subjective feelings arises from neural states that are not subjective). His theory offers an explanation for why we cannot know "what it feels like" to be a bat, but does not explain why the bat feels whatever it feels, i.e. how feelings are created from brain states.
An Impossible Science?
It was the USA psychologist Karl Lashley who first warned that… the mind is never conscious. The mind can never perceive the processing that goes on in the brain when the mind is thinking something. When I think about myself, I am not conscious of what my brain is doing. Whatever it is that I am feeling, it is not what the brain is doing. I am not aware of the billion of electrochemical processes switching neurons on and off.
One can even suspect that it is simply impossible for a conscious being to understand what consciousness is. The USA philosopher Thomas Nagel pointed out that one is only capable of conceiving things as they appear to her, but never as they are in themselves. We can only experience how it feels to be ourselves. We can never experience how it feels to be something else, for the simple reason that we are not something else. As Nagel wrote ("What is it like to be a bat", 1974), we can learn all about the brain mechanisms of a bat's sonar system but we will never have the slightest idea of what it is like to have the sonar experiences of a bat. Likewise, understanding how the human brain works may not be enough to understand human consciousness.
The Australian philosopher Frank Jackson ("Epiphenomenal Qualia", 1982) used the example of a color-blind neuroscientist who can only see black and white and, no matter how much she knows about the neurophysiology of colors, will never experience what red feels like.
The British philosopher Colin McGinn argued that consciousness cannot be understood by beings with minds like ours. McGinn believes that there is nothing "magic" about consciousness: consciousness is a natural phenomenon just like many others (lightning or hurricanes or comets) and, as such, it is a consequence of the way matter is structured and functions (specifically, how the brain works).
We are capable of understanding natural phenomena like lightning and hurricanes, but McGinn suspects that we are not capable of understanding "all" natural phenomena. There are natural phenomena that our mind cannot comprehend, just because our mind is not an infinitely powerful computer.
In a sense, McGinn’s central thesis is that our mind has limitations. Consciousness itself might be one of the phenomena that fall within the mind's limitations, i.e. fall outside the "cognitive closure" of the human mind. That does not mean that nobody can ever explain consciousness: a being equipped with a "better" mind could understand how consciousness works, where it comes from and what it is. But not our mind.
We can understand how the brain works. The brain is a natural phenomenon that we can easily investigate with our science. We will learn more and more about the brain. We will eventually work out a very detailed model of the brain. We may even be able to reproduce the brain molecule by molecule. But we will never be able to figure out how emotions arise from the unconscious matter that makes up the brain.
McGinn’s fundamental assumption is that the human mind is biased in its cognitive skills. This follows from a Darwinian view of life: all of our organs are biased, one way or another, towards coping with the environment. McGinn simply extends this principle to the mind. Our mind is very skilled at understanding spatial and temporal relationships, and at doing what we call Science. Our mind is probably not very skilled at doing things that would be useful on Mars but that do not exist on Earth. Thus it is reasonable to assume that the human mind has been designed by evolution to solve some problems better than others, and not to solve many other problems at all.
In particular, McGinn thinks that our intelligence is not designed to understand consciousness. Science is the systematic understanding of nature by the human mind, but it is limited to what the human mind can understand. There might be many things in nature that the human mind will never understand, and maybe not even perceive. Consciousness is one of them. Our brains were not biologically designed to understand consciousness. McGinn even speculates that knowledge of ourselves is useful to a limit: maybe if we could fully understand ourselves, we would get very depressed and not willing to survive anymore. Thus natural selection may have pruned away the ones who did understand consciousness, and left only the ones who could not understand it, of whom we are the descendants.
Inspired part by the British philosopher Bertrand Russell and part by the German philosopher Immanuel Kant, McGinn argues that consciousness is known by the faculty of introspection, as opposed to the physical world, which is known by the faculty of perception. The relation between one and the other, which is the relation between consciousness and brain, is "noumenal", or impossible to understand: it is provided by a lower level of consciousness that is not accessible to introspection. That is why consciousness does not belong to the "cognitive closure" of the human organism.
Understanding our consciousness is beyond our cognitive capacities, just like a child cannot grasp social concepts or I cannot relate to a farmer's fear of tornadoes. McGinn points out that other creatures in nature lack the capability to understand things that we understand (for example, the general theory of relativity). There are parts of nature that they cannot understand. We are also creatures of nature, and there is no reason to exclude that we also lack the capability of understanding something of nature. We may not have the power of understanding everything, unlike what we often assume. Some explanations (such as where the universe comes from, and what will happen afterwards, and what is time and so forth) may just be beyond our mind's capabilities. Explanations for these phenomena may just be "cognitively closed" to us. Phenomenal consciousness may be one such phenomenon.
"Mind may just not be big enough to understand mind".
McGinn speculates that consciousness might be a very ancient invention. In fact, the fact that consciousness has no spatial dimensions leads him to speculate that consciousness may have tapped into a non-spatial property that disappeared with the Big Bang (the cosmic event that created the spatial universe we live in). Our minds may be remnants of a dimension that does not exist anymore but that was pervasive in the pre-Big Bang universe.
He cunningly refutes the idea that computers can be conscious in virtue of being computers. McGinn explains that this idea is based on a bad theory of consciousness. We have no evidence that the property of running a program is the property that yields consciousness. This does not mean that conscious machines are impossible: the key is in finding out what is the property that yields consciousness, and then implementing that feature in a machine. McGinn points out that one such machine already exists: me. Thus it is feasible. Cogito, ergo I am feasible. McGinn changes the question to make it more interesting: can a machine made of inorganic material be conscious?
Implicitly, McGinn assumes that our "cognitive closure" does not change with time, that it is a constant of the human condition. On the other hand, it is obvious that it changes during the course of a lifetime: children cannot grasp concepts that adults can. One can also argue that our "cognitive closure" has evolved over the centuries, that we are more "conscious" today than we were thousands of years ago. Certainly, concepts such as democracy and women’s rights are more obvious to today’s humans than they were to even the most enlightened of the ancient Greek philosophers. Studies on ancient texts point to a reliance on gods that today has been replaced by a reliance on our own opinions. One can argue that today we "think" differently. One can argue that each generation uses knowledge of the previous generation to expand that "cognitive closure".
The question then is whether the "cognitive closure" that McGinn talks about is a temporary limitation, a "stage" in the evolution of manking, or a permanent deficiency of our mind (due, say, to the structure of the brain, or to some impossible neural connections, or to the limited capacity of our memory). Since McGinn does not "quantify" where the cognitive closure comes from, i.e. what it is physically, one cannot decide whether it can be overcome or not by future generations. If we not know what causes that cognitive closure, we cannot know whether it can be overcome.
Last but not least, one can object: if our brains were not designed to understand consciousness, why are we wondering about it? Were our brains designed to wonder about consciousness? Were our brains designed to wonder about something that we cannot possibly understand? Why?
The USA philosopher John Searle makes a two-fold claim: consciousness cannot be reduced to the neurological processes that cause it, but it is indeed a biological feature of the brain.
Brains cause minds, in his opinion, although we will not find feelings and emotions in the material processes of the brain, because feelings and emotions are higher-order features of the brain. Searle attacks the Cartesian tradition from the foundations: both dualism and materialism make no sense. The division of the world into matter and mind is arbitrary and counterproductive. In his view, we simply have to face the facts: consciousness is caused by brain processes, but consciousness cannot be reduced to those brain processes because it is a "first person" phenomenon and the brain processes are "third person" phenomena. To Searle, the mind-body problem has never existed: Descartes invented a vocabulary, a terminology, not a real problem.
In a similar vein to the school of "supervenience", Searle compares the mind-body problem to explaining how electricity arises from electrons or liquidity from molecules.
Searle is content with stating that consciousness is a (causally) "emergent" property of systems, just like electricity and liquidity. Searle realizes that liquidity can be predicted from the properties of elementary particles, whereas consciousness cannot be predicted from the properties of neurons. Searle realizes that Physics can explain how the features of electricity correspond to the features of electrons, whereas we can't explain (yet) how the features of consciousness arise from the features of neurons. Physicists can explain why (and exactly under which conditions) a set of molecules can achieve the phase transition to liquidity, whereas neurologists can’t explain when exactly non-conscious matter becomes conscious. Searle thinks that it is not just a limit of today's neurophysiology (likely to change with time), but that this will always be the case, that it is impossible to provide a material explanation of the features of consciousness. Searle thus admits a crucial difference between consciousness and electricity or liquidity or digestion: consciousness is special in that it cannot be explained.
Searle has nothing to offer other than declare that mental life exists and that it emerges from neurons, which is equivalent to saying that liquidity exists and that it emerges from liquids.
Searle thinks that computers have no minds because they are not brains, but he never proves the underlying assumption: that they are not brains. In Searle's jargon, "brain" is simply the "thing" that enables the mind. His entire theory can therefore be viewed a mere tautology: the mind is due to the thing that causes it. What that thing is, it remains a mystery. Ultimately, Searle merely states that the mind exists. If one has not defined what a brain is, it is hard to claim that something is not a brain.
Searle basically resurrects Thomas Nagel's argument that consciousness cannot be explained. Thus consciousness is not an emergent process like liquidity, because liquidity, like all emergent properties, is reducible to the physical process that creates it. Emergent properties are normally predictable by science: we know when (and why and how) a substance is a liquid and not a solid or a gas. If consciousness is indeed an emergent property, why should it be the only one that we cannot predict and explain?
Searle is not baffled by the emergence of conscious feelings from unconscious neurological processes of the brain. He finds it perfectly understandable. And therefore he downplays and ridicules all theories that tried to solve this paradox. But it is like somebody not being puzzled by the fact that the sun rises and sets every day, and contenting himself with the idea that it must be a feature of the Earth.
The Classical Theory of Consciousness
William James (at the end of the 19th century) was responsible for articulating the "classical" theory of consciousness, the equivalent of Newton's classical Physics. To James, consciousness is a sequence of conscious mental states, each state being the experience of some content. Just like Newton saw a unitary and continuous space, James saw a unitary and continuous consciousness.
James thought that consciousness must have an evolutionary purpose, just like Darwin thought that all features of the body must have an evolutionary purpose. Thinking is useful for our survival, just like eating and mating. James treated consciousness like a function, not an entity.
James was, in part, reacting to the theory of perception that dated from the 19th-century German physicist Hermann von Helmholtz, that sense data from the senses are turned by the "mind" into percepts which are conscious experiences of the environment. James thought, instead, that the output of brain processes is guidance of action in the environment, not a conscious experience of the environment.
Furthermore, James realized that every act of perception specifies both a perceiving self and a perceived object. Seeing something is not only seeing that object: it is also seeing it from a certain perspective. The perspective implies a "seer". A sensory act specifies not only the environment but also the self. Self (the "subjective") and environment (the "objective") are two poles of attention. Each act of perception specifies both the self and the environment.
The self, in turn, is one but is also divided. The self is partly object and partly subject: there is a self who is the knower (the "I") and a self who is the known (the "me").
Consciousness in the Environment
In the 1930s the USA biologist George Herbert Mead put forward a theory that, instead, located consciousness in the world, outside the organism.
For Mead, consciousness is not a separate substance, but the world in its relationship with the organism. Objects of the environment are colored, beautiful, etc: that "is" consciousness.
Objects do not exist per se: they are just the way an organism perceives the environment. And, presumably, different organisms may perceive different objects. Each organism perceives a different environment. It is our acting in the environment that determines how we perceive the environment. We are actors as well as observers. The response of the environment is what we perceive as objects.
In other words: the nature of the environment lies in its relationship to the organism; the environment results from the actions of the organism, in response to the stimulation of its sense organs, i.e. the organism determines the environment; and this results in the appearance of objects.
We are programmed to pick up organized information about the environment in the form of objects. The environment we perceive is merely a perspective of the real environment (that Mead calls "habitat"), one of the many that are possible. Each organism gets a different environment from the same habitat. The one world that we living beings inhabit is perceived in different ways (as different environments) by different organisms. This perspective is determined by the actions that the organism is capable of, by the set of its "organized responses". In particular, any change of the organism results in a change of the environment.
The organized objects of the environment actually represent our organized responses. They are what exists for us (for the kind of responses we are capable of). There is a direct relationship between our repertory of actions and our view of our habitat. Ultimately, the environment is a property of the organism as well as of the habitat. Those objects have qualities (such as colors) and values (such as beauty) that constitute what we call "consciousness". But, again, those objects and therefore their qualities depend on our repertory of actions.
Consciousness is a function, not a substance, and it refers to both the organism and the environment. It is located in the organism's environment, not in the organism's brain.
Consciousness is not a brain process: the switch that turns consciousness on or off is a brain process. Pulling up the blinds of a window does not create the street, it merely reveals it. By the same token, the brain can "pull up the blinds" and reveal consciousness, i.e. the set of objects and their qualities. Or it can pull them down, and consciousness disappears. The brain only has control over this switch.
Everybody has this kind of consciousness, but some species (and the children of our own species) cannot report on their experiences. It is social experience that makes awareness possible. It is not consciousness that enables socialization: it is socialization that enables consciousness (as awareness of one's experience).
The self is created through socializing. A self is a contributor to awareness, and is aware of all contributions. A self always belongs to a society of selves. And a self is what he is as a member of that society of selves.
Likewise, the USA biologist James Jerome Gibson used vision to explain what awareness is and what it is not. Body and mind constitute a false dichotomy. Awareness is both physical and mental. Awareness is a function performed by a living observer, the whole living being, not just its mind or its body. Awareness is a biological phenomenon. Perceiving is keeping in touch with the world. The observer is not external to the world, and therefore her/his awareness cannot be a state outside the world (i.e., in a different substance called "mind"). Cognition is a biological phenomenon, and it is both mind and body. Awareness is both mind and body.
Sensing the Brain
Several models of consciousness focus on its behavior as a "sense" capable of perceiving the processing of the brain.
The British philosopher Nicholas Humphrey argued that to be conscious is to feel sensations, as opposed to perceptions. Animals have developed two ways of representing the interaction between the body and the world: "affect-laden" sensations and "affect-neutral" perceptions. Sensation and perception are separate and parallel forms of representation. Sensations are to be found at the boundary between the organism and the world and at the boundary of past and future. One "senses" a circle of light hitting the retina; one "perceives" the sun in the sky. One can have sensations about perceptions and perceptions about sensations.
Humphrey ("The Use of Consciousness", 1967) speculated that we possess an "inner eye" that behaves like any other sense, except its object is the brain itself. This inner eye evolved because it was useful, and it evolved in such a way as to be useful. Therefore it does not deliver a one-to-one picture of the brain's activity, but a selected, abridged and biased one, as useful to survival as possible. Consciousness allows me to perceive the state of my brain as conscious states.
The USA philosopher William Lycan is a proponent of consciousness as "internal monitoring", an idea that reaches back to the British philosopher John Locke and the German philosopher Immanuel Kant. Lycan emphasizes that most of our mental life is unconscious, that we are conscious of only part of it. A possible explanation is that consciousness is a perception of our own psychological state, of what is going on in the mind (Kant's "inner sense").
The British neurophysiologist John Eccles believes that consciousness resides in a psychological world that transcends the physical. Eccles believes that the mind is an independent entity that exercises a controlling role upon the neural events of the brain by virtue of its interaction across the interface between World 1 (the physical world) and World 2 (the mental world). The mind is continuously searching for brain events that are interesting for its goals.
The USA linguist Ray Jackendoff believes that there are three main entities that account for our mental life: the physical brain, the computational mind (cognition) and the phenomenological mind (consciousness). The computational mind is the one that really "thinks", whereas the phenomenological mind only "feels" superficially a subset of the "thoughts". Most of "thinking" is actually unconscious. We are never conscious of the outer world, but only of the shadows of some of the processing that the computational mind does on the outer world. Consciousness arises from a level of representation that is intermediate between the sense-data and the form of thought, at the border between the representations of the inner and of the outer worlds.
The USA psychologist Owen Flanagan does not believe in "one" consciousness, but in a group of "conscious" phenomena. Some of the processes of our body are unconscious and non-perceived (e.g., the heartbeat), while some are unconscious but perceived by other processes (sensors), and some are conscious, perceived by themselves. Consciousness is a heterogeneous set of processes, not a substance or an object. Flanagan’s theory is, de facto, a variation on William James’ stream of consciousness: there is no "Mind’s I" that thinks and is conscious, that are just thoughts that flow. Consciousness is not: consciousness flows. "The thoughts themselves are the thinkers". I do not think thoughts, thoughts think me. There is no "I": there is conscious activity. This conscious activity differs from the neural activity only in kind, but the mind "is" the brain.
Binding Brain and Consciousness
Knowledge about the world is distributed around the brain. How it is then integrated into one unitary perception is the "binding" problem.
This problem occurs at several levels. A sensory input is channeled through several different areas of the brain, each brain region focusing on one aspect of the input, but then somehow the mind perceives the whole input as something that happens at the same time in the same place, and it is a whole. The "binding" problem refers to how the brain creates the whole perception out of a sensory input that has been fragmented around the brain.
For example, a visual input is "split" so that one brain region analyzes the shape and one brain region analyzes the color. But somehow these separate pieces of information are joined again to produce the overall sensation of the image. At a higher level, different sensory inputs come together: the sound of an event is merged with the image of the event, or the smell of the event, or the touch of the event. The result is the overall feeling of the situation.
At an even higher level, the situation is merged with pre-existing memories and concepts. We don't only see a human being moving and speaking around us: we see our friend X talking to us. At the highest level, this entire complex system of feelings and knowledge "feels" unified in our consciousness. There is "one" feeling of "me" existing in a "world". Somehow all has been "bound" together into consciousness.
There are different theories about where and how and when this ultimate form of "binding" could occur.
"Space-based binding" is advocated by scientists who believe that there is a specific place in the brain where all information is integrated together. In the 1990s, a competing paradigm has emerged which is based on time instead of space, and is therefore referred to as "time-based binding": there is no particular place where the integration occurs, because integration occurs over the entire brain, and is regulated by some periodic process.
Space-based binding theories try to identify the "homunculus" in the brain that is responsible for running the integration process.
The working memory is a popular candidate for such a task, but no piece of the brain seems likely to show us the transformation of electrochemical processes into "feelings" (conscious processes).
According to the Portuguese neurobiologist Antonio Damasio, the story is more complex. There is not just one working memory: there is a whole system of "convergence zones". The brain has "convergence zones" and convergence zones are organized in a hierarchy: lower convergence zones pass information to higher convergence zones. Lower zones select relevant details from sensory information and send summaries to higher zones, which successively refine and integrate the information. In order to be conscious of something, a higher convergence zone must retrieve from the lower convergence zones all the sensory fragments that are related to that something. Consciousness of something occurs when the higher convergence zones fire signals back to lower convergence zones.
The Movie in The Mind
Damasio breaks the problem of consciousness into two parts: the "movie in the brain" kind of experience (how a number of sensory inputs are transformed into the continuous flow of sensations of the mind) and the self (how the sense of "owning" that movie comes to be).
The "core" consciousness of the "movie in the brain" is essentially unchanged throughout a lifetime, and humans share it with many other species.
On the other hand, the "extended" consciousness of the self is refined over a lifetime: an "owner" and "observer" of the movie is created within the core consciousness, in such a way that it seems to be located outside the brain, while it is part of the brain's neural processes and part of the movie itself which those neural processes generate. The more developed the sense of the self, the stronger the impression that the movie in the mind is "my" experience of the world.
Distinct parts of the brain work in concert to represent sensory input. Brain cells represent events occurring somewhere else in the body. Brain cells are "intentional" (the philosophical "intendo"): they represent something else in the body. They are not only "maps" of the body: besides the topography, they also represent what is taking place in that topography.
Indirectly, the brain also represents whatever the organism is interacting with, since that interaction is affecting one or more organs (e.g., retina, tips of the fingers, ears), whose events are represented in brain cells.
These two "orders" of representation are crucial for the rise of consciousness.
The "movie in the mind" is a purely non-verbal process: language is not a prerequisite for this first level of consciousness. The "I" is a verbal process that arises from a second-order narrative capacity.
The brain stem and hypothalamus are the organs that regulate "life", that control the balance of chemical activity required for living, i.e. the body's homeostasis. Consequently, they also represent the continuity of the same organism.
Damasio believes that the self originates from those biological processes: the brain is equipped with both a representation of the body, and a representation of the objects the body is interacting with. Thus it can discriminate self and non-self, and generate a "second order narrative" in which the self is interacting with the non-self (the external world). This second-order representation occurs mainly in the thalamus.
More precisely, the neural basis for the self resides in the continuous reactivation of 1. an individual's past experience (which provides the individual's sense of identity) and 2. a representation of the individual's body (which provides the individual's sense of a whole). An important corollary is that the self is continuously reconstructed.
From an evolutionary perspective, we can presume that the sense of the self is useful to induce purposeful action based on the "movie in the mind". The self provides a survival advantage because the "movie in the mind" acquires a first-person character, i.e. it acquires a meaning for that first person, i.e. it highlights what is good and bad for that first person, a first person which happens to be the body of the organism, disguised as a self.
This second-order narrative derives from the first-order narrative constructed from the sensory mappings. In other words, all of this is happening while the "movie" is playing. The sense of the self is created, while the movie is playing, by the movie itself. The thinker is created by thought. The spectator of the movie is part of the movie.
Consciousness is an internal narrative, due to those mappings. The "I" is not telling the story: the "I" is created by stories being told in the brain ("You are the music while the music lasts").
Consciousness As Self-Reference
The idea of some form of "self-referential feedback" (of some kind of loop inside the brain) is firmly rooted in modern space-based binding theories. Gerald Edelman's "reentrant maps" and Nicholas Humphrey's "sensory reverberating feedback loop" are variations on the same theme. The idea is that, somehow, the brain refers to itself, and this self-referentiality, somehow, unchains consciousness. Rather than "space-based", these theories tend to be "process-based", since they are not only looking for the place where the binding occurs but also for the way it occurs, and the process turns out to be much more important than the place.
According to Edelman, consciousness is a natural development of the ability to build perceptual categories (such as "blue", "tall", "bird", "tree", "book"), the process that we normally call generalization. The brain can do this because neurons get organized by experience in maps, each neural map dealing with a feature of perceptions (color, shape, etc.).
First of all, Edelman distinguishes between primary consciousness (imagery and sensations, basically being aware of things in the world) and higher-order consciousness (language and self-awareness).
For primary consciousness to appear a few requirements must be met. It takes a memory, and an active type of memory, that does not simply store new information but also continuously reorganizes (or "re-categorizes") old information. Then it takes the ability to learn, but learning is not only memorizing, it is also a way to rank stimuli, to assign value to stimuli (a new value will result in a new behavior, and that is what learning is about). Then it takes the ability to make the distinction between the self from the rest of the world, i.e. a way to represent what is part of the organism and what is not. Then it takes a way to represent chronology, to order events in time. Finally, it takes a maze of "global reentrant pathways" (i.e., forms of neural transmission that let signals travel simultaneously in both directions) connecting all these anatomical structures. Primary consciousness arises from "reentrant loops" that interconnect "perceptual categorization" and "value-laden" memory ("instincts"). In general, cognitive functions emerge from reentrant processes.
Consciousness therefore arises from the interaction of two parts of the neural system that differ radically in their anatomical structure, evolution, organization and function: the one responsible for categorizing (external stimuli) and the other responsible for "instinctive" behavior (i.e., homeostatic control of behavior). Consciousness emerges as the product of an ongoing categorical comparison of the workings of those two kinds of nervous system.
From an evolutionary point of view, the milestone moment was when a link emerged between category and value, between those two different areas of the brain. That is when the basis for consciousness was laid.
A higher-level consciousness (being aware of itself), probably unique to humans, is possible if the brain is also capable of abstracting the relationship between the self and the non-self, and this can only happen through social interaction, and this leads naturally to the development of linguistic faculties. Edelman identifies the regions that are assigned to define self within a species (the amygdala, the hippocampus, the limbic system, the hypothalamus) and those that operate to define the non-self (the cortex, the thalamus and the cerebellum).
Note that, according to Edelman, concept-formation preceded language. Language was enabled by anatomical changes. What changed with the advent of language is that concepts became independent of time, i.e. permanent. And semantics preceded syntax: acquiring phonological capacities provided the means for linking the preexisting conceptual operations with the emerging lexical operations.
In Edelman's picture, consciousness is liberation from the present. Animals tend to live in the present, simply reacting to stimuli. Only conscious animals can think about the past and about the future.
As for the "place" where consciousness happens (its neural correlate), Edelman noted that consciousness is unified and a "whole", while nothing in the brain seems to be unified and a "whole": in fact, the brain is made of a multitude of regions that exhibit independent personalities. Consciousness must therefore be due to a global process that encompasses more than one region. He believes that the thalamocortical system originates such an activity: a massive, coherent (synchronized) activity by all regions of the brain, that transcends the individual activity of each region. Basically, consciousness is a process that happens throughout the brain, not manufactured in a specific region.
The location of consciousness is changing all the time, as different groups of interacting regions form and dissolve. At any moment in time, the "dynamic core" of primary consciousness is located in the interaction between the thalamus and the cortex. He does envision one particular region as being the permanent site of consciousness. In a sense, consciousness is the "process" not the "place".
The Mundane Components of Consciousness
British neurologist Adam Zeman showed how mundane consciousness is: a little more or less of this or that chemical makes a big difference on how you "feel". Consciousness depends, mostly, on events that take place within the brain. A lack of this or that chemical is enough to alter our personality. After all, consciousness is a product of neural activity, and neural activity is a material process that uses material elements, which, ultimately, are the (indirect) constituents of consciousness.
By the same token, he describes perception as the brain’s reaction to being bombarded with energy picked up by the body’s sensors. Without that external energy, there would be no visual or auditory or whatever processing. Whatever the brain does, it is initiated by an energy impulse coming from the outside. It is then processed according to the chemical structure of the brain, which, by definition, depends on the amount and kinds of chemicals in the brain.
Zeman is quite convinced that the thalamus is the central site of consciousness. During sleep, the thalamus interacts with the cortex in rhythmic bursts, while inhibiting all sensory inputs. When the body is awake, the thalamus works as an intermediary between the periphery and the cortex, shuttling back and forth sensory inputs and commands to move. The brainstem is the switch that turns the thalamus on and off.
Zeman’s experiments raise the issue of whether consciousness is really a whole that cannot be reduced to components. Different neurotransmitters seem to contribute to different aspects of consciousness. If a neurotransmitter is inhibited, the person is affected, both physically and emotionally. If each neurotransmitter helps shape consciousness, can’t we also claim that consciousness is not a whole but, trivially, a sum of its parts?
Time-based binding does not look for the "place" but for the "time" at which the binding of our conscious experience occurs.
The German physicist Christof Koch ("Collective Oscillations in the Visual Cortex", 1989) discovered that at, any given moment, very large number of neurons oscillate in synchrony, reflecting something that was captured by the senses, but only one pattern is amplified into a dominant 40 Hz oscillation. That is the "thing" the individual is conscious of. Out of so many oscillations of synchronized cells in the brain, one is special and happens to have a frequency of 40 Hz.
The USA biologist Charles Gray then hypothesized ("Synchronous Oscillations in Neuronal Systems", 1994) that the memory of something is generated by a stream of oscillating networks. Separate brain regions (corresponding to different categories of features) send out nervous impulses at the same frequency and the perception of an object is created by the superimposed oscillation. The brain uses frequency as a means to integrate separate parts of a perception. In this way the limited capacity of the brain can handle the overwhelming amount of objects that the world contains (the number of objects we see in a lifetime exceeds the number of neurons in the brain that would be needed to store them as images).
This theory is compatible with both Damasio's and Edelman's theories, as they all posit some type of "synchrony" for consciousness of something to emerge. According to these theories, it is time, not space, that binds.
Time-based binding almost marks a revival of "gestalt" psychology (the oscillation is, for practical purposes, a gestalt).
An Independent Brain
The Colombian neurophysiologist Rodolfo Llinas has interpreted these findings as a scanning system that sweeps across all regions of the brain every 1.25 thousandths of a second (40 times a second). The region of the brain containing the information about a sensation constitutes the "context" of an instance of conscious experience. The 40Hz oscillation provides the "binding" of such content into a unified cognitive act.
This wave of nerve pulses is sent out from the thalamus and triggers all the synchronized cells in the cerebral cortex that are recording sensory information. The cells then fire a coherent wave of messages back to the thalamus. Only cortex cells that are active at that moment respond to the request from the thalamus. Consciousness originates from this loop between thalamus and cortex, from the constant interaction between them. Consciousness is generated by the dialogue (or "resonating activity") between thalamus and cortex.
Consciousness is simply a particular case of the way the brain works. Other brain regions have their own temporal binding code. The motor system, for example, works at 10 cycles per second (which means that movements only occur ten times a second, not continuously). Every function is controlled by a rhythmic system that occurs automatically, regardless of what is happening to the body. Consciousness happens to be the phenomenon generated by that specific rhythmic system that operates on the brain itself.
Besides the 40-cycle-per-second, the brain has a number of natural oscillatory states: at 2 cycles per second it is sleeping. One of the brain's functions is to create images: at 2 cycles per second it creates dreams; at 40 cycles per second it creates images that represent the outside world as perceived by the senses.
In other words, the brain is always working independently of what is happening outside: during sleep, i.e. in the absence of sensorial data, that work is called "dreaming"; during the day, in the presence of sensorial data, it is called thought. The difference is that the brain’s automatic dreaming is conditioned by the senses: when the senses are bombarded by external stimuli, the brain can generate only some types of thought, just like the body can generate only some types of movement. At every instant, the brain is dealing with both reality and fantasy. "A person's waking life is a dream modulated by the senses".
The USA neuroscientist Paul Churchland provided a detailed description of how the brain perceives sensory input (in particular vision) through what he calls "vector coding". He claims that consciousness must be based on a "recurrent" network, and Koch's 40 Hz oscillation in the cortex is a convenient candidate for a brain-wide recurrent network. That brain-wide recurrent network would be able to unify the distinct senses in one consciousness.
In this sense, therefore, consciousness does not require language, and non-linguistic animals can be conscious too. Consciousness is biological, not social (its contents may be social, such as language).
The Neuronal Correlate of Consciousness
The British biologist Francis Crick too subscribes to the view that synchronized firing in the range of 40 Hertz in the areas connecting the thalamus and the cortex might explain consciousness; that consciousness arises from the continuous dialogue between thalamus and cortex. Awareness of something requires "attention" (being aware of one object rather than another), and attention requires "binding" (banding together all neurons that represent aspects of the object). Crick believes that binding occurs through a synchronous (or "correlated") firing of different regions of the brain. During attention, all the neurons that represent features of an object fire together. It is not just the frequency of firing of the neurons that matters, but the moments when they fire. The main difference between Llinas and Crick is in their background. Crick studied visual awareness and so is interested in consciousness that arises from external stimuli. Llinas, on the contrary, is more interested in consciousness that does not arise from external stimuli (what we call "thought").
The German neurologist Christof Koch tried to relate this to the neural activity in the brain. One of the first clues (although apparently disconcerting) is that much of the neural activity of the brain is not conscious at all: we are not aware of most of what our brain does. Most of the time (e.g., habits, instinct, etc.) the brain makes key decisions without "us" being conscious of those decisions. Koch and Crick focus on the "neuronal correlates of consciousness" (NCC): the "thing" in the brain that corresponds to states of awareness. Because most neuronal activity does not yield a state of awareness, they are led to believe that multiple forms of neuronal activity exist (this is almost a tautology). They believe that one could potentially be conscious of many competing views, but only one "wins" the competition and results in awareness of the corresponding view. The first clue to find these NCCs is the way they represent the external world. All body cells are, to some extent, influenced by what happens to the body, but only a minority of the body cells represent external stimuli in an "explicit" manner: Koch and Crick believe that one is only conscious of features that are encoded "explicitly" by some neuronal assembly. The other way to find them is to listen to the way they oscillate. The electric potential of the brain as a whole exhibits oscillatory behavior in different frequency bands: the dominant rhythm for resting individuals is in the "alpha" band (8-12 Hz); the rhythm for normal cognitive activity is in the "beta" band (15-25 Hz) or, for more complex operations, in the "gamma" band (30 Hz or higher); sleep is in the "delta" band (1-4 Hz). Each of these "oscillations" is caused by some synchronous behavior ("firing") of many neurons.
The "binding" problem is the problem of how the various features are integrated in the brain into the perception of the object as a whole, especially when the same brain is integrating other features of other objects. The German physicist Christoph von der Malsburg ("How are Nervous Structures Organized?", 1983) was the first to propose that synchronization could be the solution to the "binding" problem: the neurons working on one object are synchronized, and they are not synchronized with other populations of neurons that are working on other objects. There is one oscillatory behavior by neurons that seems to be associated with awareness, and it is in the 30-70 Hz range, with a peak around 40 Hz. In 1990 Koch and Crick claimed that this oscillation accounts for consciousness (i.e., that the set of those synchronized neurons "is" the NCC for the current state of awareness).
Koch and Crick believe that several such "coalitions" of neurons exist at every point in time, and a sort of Darwinian selection determines which one (and only one) wins and results into awareness.
Another clue to finding the NCC is the cholinergic system: consciousness only occurs when there is an adequate supply of acetylcholine neurotransmitters, which are regulated by the brainstem (people whose brainstem is damaged lose consciousness).
The brain has a convoluted structure, and the way it represents an experience is even more convoluted, but we perceive an experience as a sequential of events. Koch thinks this has to do with the fact that, at every point in time, only one coalition is the winning one. It may change all the time, but we perceive an ordered sequence of events, because every other coalition that is active at the time is suppressed. We do not perceive the convoluted activity of the brain, which is analyzing an overwhelming amount of data, but only those events that correspond to the winning coalition.
Koch divides short and long-term memory based on the underlying mechanism: long-term memory is caused by a physical rewiring of the brain (strengthening of connections), whereas short-term memory is caused by a sustained firing pattern by an assembly of neurons. Koch proves that consciousness depends on the latter, not on the former. Short-term (or, better, working) memory could provide a sort of "Turing test for consciousness": any being that displays a working memory is likely to be conscious.
Koch also speculated on why we are conscious at all. After all, we do not need consciousness: the brain makes most of the key decisions in an unconscious way. The autonomic system directs the organs to do their job, and "instinct" helps the body survive. Qualia (the qualitative aspects of things) are "symbols" that help the brain synthesize, summarize, huge amounts of data. Seeing red or feeling pain are shortcuts to handle huge amounts of sensory data. Qualia are symbols that summarize the state of the world (including the body itself). This is the "executive summary hypothesis".
Koch believes in a non-conscious homunculus, residing in the front of the forebrain, that handles the information stored in the back of the cortex (the sensory regions) and that does all of the "thinking". The front of the cortex is looking at the back. This homunculus is beyond consciousness, the same way that automatic, zombie-like behavior is beyond consciousness, although one is "above" it (supramental) and the other is "below" it (submental). Consciousness is an intermediate level, which is conscious not of the homunculus and its work (its "thoughts") but only of representations of the homunculus' work in the form of inner speech.
Consciousness resides at an intermediate level, which is conscious not of the homunculus and its work (its "thoughts") but only of representations of the homunculus' work in the form of inner speech. We are not conscious of the homunculus that is making decisions for us, and we are not conscious of the real world. We are only conscious of reality that we manufacture.
What Edelman and Llinas have in common is the belief that higher mental functions originates from a process of loops that reverberate through the brain (in particular, between the thalamus and the cortex, the thalamus being the source of so many crucial signals and the cortex being the newer, more sophisticated part of the brain). Their theories differ in the specific mechanism but they both focus on the fact that regions of the brain are connected in a bidirectional way and that they "resonate" to each other, they are somehow in synch.
There are other models that exploit the same paradigm.
The Chilean neurologist Francisco Varela has claimed that there is a primary consciousness common to all vertebrates. This primary consciousness is not self-awareness but merely experience of a unitary mental state. Varela thinks that it is due to a process of "phase locking": brain regions resonate, their neurons firing in synchrony, and create a cell assembly that integrates many different neural events (perceptions, emotions, memory, etc). This coherent oscillation of neurons is primary consciousness.
The USA physicist Erich Harth tried to explain consciousness by means of a process that relies on "positive" feedback. Feedback can be negative or positive. Negative feedback is the familiar one, which has to do with stabilizing a process, in particular the input with the output of the process (e.g., thermostats and car engines). Positive feedback works in the opposite direction, at the edge of instability: the signal is amplified by itself, weakening the relationship between input and output. Harth thinks that a loop of positive feedback spreads through different areas of the brain and provides "selective amplification". The loop basically joins the thalamus and the cortex, so that both send outputs that are inputs to the other. When input from the thalamus is stronger, the external world prevails. When input from the cortex is dominant, cognition prevails.
The British neuroscientist Susan Greenfield derived a definition of consciousness from her studies of mental infirmities: consciousness is the process of propagating a stimulus through a network of connected neurons, the same way one perceives the widening ripples created by an object falling in a pond.
She believes that, while there is no integrator of consciousness in the brain, nonetheless some type of "temporary" localization must exist. There is no site of consciousness, but consciousness originates from processes happening locally somewhere sometime. She believes that different groups of neurons take over at different times, a picture that resembles theories by Michael Gazzaniga and Daniel Dennett. Therefore, "consciousness" is multiple in space but unitary in time.
These groups of neurons she calls "gestalts": highly dynamical and transient, they are created by some kind of "arousal" and they are localized around an "epicenter".
She calls them "gestalts" because the dynamic properties of the brain "emerge" in a "gestalt" fashion from the connectivity of such neuronal assemblies.
An arousal can be an external (sensory) phenomenon or an internal (cognitive) phenomenon. The arousal causes the formation of a "gestalt" around an epicenter. The gestalt causes the "emergence" of a conscious event.
Each instance of consciousness arises from such a gestalt, caused by an arousal and localized around an epicenter. Overall consciousness develops from epicenters spread around the brain.
The passage from one conscious event to another conscious event, from one gestalt to another gestalt, which is typical of our inner life, is due to a ripple effect: the ripples of one gestalt's concentric action may act as an arousal and trigger another gestalt.
The size of a gestalt depends, first of all, on the strength of the arousal. But it also depends on the power of the epicenter to recruit neurons, a power that in turn depends on rival gestalts that all compete for neurons. The size of the gestalt has a direct meaning for us, because it corresponds to the depth of consciousness, to the intensity of the feeling.
During growth, epicenters tend to shift from "outside" to "inside", from external stimuli to internal associations.
Mental life is a dual process of searching for information and adaptation to information, the former leading to more conscious access, the latter reducing conscious access (things become habitual and automatic).
Consciousness "grows" as the brain does (from fetus to neonate to child to adult).
The Paradox of Attention
Attention is the process by which we focus on something. This sounds like an oxymoron, because the brain is always reacting to everything. Therefore it can't focus on "something". The sheer amount of data that enters the brain at every second is a distraction.
The brain is always processing everything that comes in, whether from the eyes or from the ears. The brain behaves like a machine reacting to all the inputs it receives. It doesn't have a choice: those inputs are transformed into electrochemical messages that cause electrochemical reactions spreading from the senses to the inner units of the brain. Limiting the brain's work to just one of these electrochemical processes is impossible. All the processes are going on at the same time, just because data hit our senses, and just because the senses always send signals to the brain, and just because every signal causes processing in the brain.
That is why, when we are driving and looking for a street in an unfamiliar neighborhood, we often turn down the radio. We cannot control the processing of the brain but we can control what data enter the brain.
Attention is a contradiction in terms.
The Cartesian Theater
The Dutch psycholinguist Bernard Baars believes that conscious experience is distributed widely throughout the nervous system and ultimately originates from a Darwinian process of selection applied to experience.
Consciousness creates access to a large amount of knowledge, or, more precisely, to a large number of unconscious sources of knowledge. When I am conscious of typing words into a computer, I am not aware of the keyboard, of the fact that computers are machines, of the movement of my fingers and of many other things, although each of those is essential to perform this task. All that knowledge exists, but is unconscious. Consciousness is very limited in how many things it can do (be conscious of) and for how long (it can keep them in short-term memory). But the brain as a whole does not have those limitations. Consciousness is a "gateway" to the vast knowledge stored in the brain.
In order to explain how this works, Baars employs the metaphor of a "theater".
Baars views the nervous system as a set of independent intelligent agents that broadcast messages to each other through a common workspace (just as if they were writing on a blackboard visible to every other agent). That workspace, the stage of the theater, is consciousness. Any conscious experience emerges from cooperation and competition between the many processing units of the brain working in parallel. The mind originates from the work of many independent, specialized "processors", i.e. skills that have become highly practiced, automatic and unconscious.
There are two sets of unconscious processes: the ones backstage, that, like the playwright and the director, determine what is played on the stage, and the ones in the audience, that capture what is being played. Whenever consciousness of something is created, the "audience" retrieves knowledge about that something. Consciousness is the gateway to the unconscious processes of the brain just like the stage is the gateway to the audience. Through consciousness, the backstage processes broadcast a message to all the spectator processes.
Baars emphasizes the striking differences between conscious and unconscious processes: unconscious processes are much more effective (e.g., we parse sentences unconsciously all the time, but cannot consciously describe how we parse them), they operate in parallel (whereas we can only have one conscious process at the time), they appear to have almost unlimited capacity (conscious processes have very limited capacity).
The conscious "stage" interacts with several unconscious "experts" that create goals and plans and compete for playing them on the stage. These experts are "modules" (eyesight, fear, hunger, etc) that compete for access to the "global workspace". A form of "natural selection" decides which module (or modules) is predominant at any time.
Consciousness is the stage, and the modules are the actors. Actors are competing for the spotlight.
The Social Brain
The USA neurophysiologist Michael Gazzaniga, a disciple of Roger Sperry (the psychologist commonly associated with the discovery of the "split brain") showed that the brain has a modular organization, whereby many independent systems work in parallel.
These "specialized" modules are evolutionary additions to the brain: it is no surprise that they perform different functions, and it is not surprising that those functions are useful to the overall functioning of the brain.
Split-brain surgery had already proved that the human brain is made of at least two brains (the two hemispheres). Gazzaniga simply extended that idea.
Basically, he thinks that many minds coexist in a confederation. Our behavior is due to the activity of these modules, rather than to conscious decisions.
A special module, the "interpreter", located in the left hemisphere, interprets the actions of modules and provides explanations for our behavior. However, that happens after the unconscious modules have already determined our behavior. Beliefs do not precede behavior: they follow it. They are created by the interaction of the interpreter with the other modules. Behavior determines our beliefs, not the other way around. It is only by behaving that we conceptualize our selves, that we build a theory of our psychological state (in particular, beliefs).
Ultimately, mental life (the life of the interpreter) is the reconstruction of the independent operations of many brain systems.
There are many "I"'s and then one "I" that makes sense of what all other "I"'s are doing.
Initially, Gazzaniga took issue with the view of the "specialized" hemispheres. It is not true that the two hemispheres are highly specialized units, and that language is "localized" in the left hemisphere: the only thing that is "lateralized" is language, and language uses up space within an hemisphere to the expense of non-linguistic features of that hemisphere. Lateralization (the fact that each hemisphere is endowed with capabilities that the other hemisphere lacks) is not specialization.
Gazzaniga and his associates also discovered that an experience has multiple aspects which are stored at different places in the brain. These memory locations are coherent but do not seem to communicate with each other.
The only way for the brain to realize its whole knowledge is for it to watch itself as it behaves. Therefore, behavior must be the source of communication between modules. Once a memory system causes behavior, the other memory systems become "aware" of those impulses/knowledge coming from the memory system that caused the behavior to occur.
Then Gazzaniga reached another important conclusion: the conscious self is not aware of our actions before we perform them but only afterwards, although it "thinks" that it caused the action. Inspired by the 1956 theory of "cognitive dissonance" by the USA psychologist Leon Festinger, Gazzaniga concludes that one of the selves, the verbal self, keeps track of what the person is doing and from that interprets reality. As Festinger originally put it, the sense of reality arises as a consequence of considering what one does.
Gazzaniga postulates the existence of multiple mental systems in the brain, each with the capacity to produce behavior. During growth one mental system, the verbal one, grows to "oversee" the others. The mind is not a psychological entity but a sociological entity. Language allows us to create a personal sense of conscious reality out of multiple mental realities.
The job of the verbal system is to make sense of mental activity and therefore provide the illusion of the self, when in reality there exists a conglomerate of selves.
There is still a puzzle, though, in Gazzaniga’s theory: if different brain regions are perfectly capable of providing good reactions to the various situations we encounter, why is there any need for consciousness at all to make sense of the world? Why is there a need for an "interpreter"? (And one that, according to Gazzaniga's findings, makes all sorts of mistakes). If consciousness has no effect on the working of these brain regions, then it's difficult to imagine why it would appear over the course of evolution. If it does have an effect, then Gazzaniga cannot claim that it is merely an "interpreter"...
Reacting to the identity theory, the USA psychologist Robert Ornstein developed his "multi-aspect" theory of the mind: the mental has an experiential (the experience of feeling a feeling), a neural (the corresponding brain processes), a behavioral (the related action) and a verbal (the related utterance) aspect.
The human mind is viewed by Ornstein as many small minds, each operating independently and specialized in one task. In other words, the body contains many centers of control. The lower level ones developed millions of years ago for basic survival activities, and humans share them with other animals. The most recent ones (e.g., the cortex) deal with decisions, language, reasoning. The brain is not a single whole, it is a confederation of more or less independent brains.
The goal of the mind is to simplify, to reduce the complexity of the external world to what is useful for the body. Minds are, therefore, attracted only to four types of events: recent events, unusual events, relevant events, events that can be compared to other events. When information is meaningful, it gets organized (i.e. simplified). That is the role played by the mind for the benefit of the body.
The mind is an adaptive system that has been shaped by the world. It is the way it is because the world is the way it is.
Human minds are initially endowed with many possible ways of evolving (e.g., with the capability for learning many possible languages), but only some are pursued and the other skills are lost during growth. The mind could potentially adapt to many different environments, but will actually adapt only to the ones it is exposed to. During development, a number of specialized, autonomous centers of action develop. These "minds" within the mind compete for control of the organism. Each one tends to stay in place for as long as possible, with its own memories and goals, until the circumstances favor the takeover of another mind.
In a sense, this is a Darwinian model, very similar to Edelman's model for the neural structure of the brain. There are many selves that take control of the brain and succeed or fail based on natural selection. Some die out, and some get stronger, depending on how often they succeed.
The USA philosopher Daniel Dennett believes that, despite the apparent unity and continuity of our experience, consciousness is non-localized and non-linear. "Non-localized" means that there is no place where it happens. "Non-linear" means that it is not a flow of feelings.
Dennett argues that the time-scale of some cognitive processes rules out the possibility that perceptions are integrated in a "Cartesian theater" in the brain before action is generated (the Cartesian theater is a metaphor for the idea that there is a central locus in the brain that directs consciousness). Despite the apparent unity of our experience, consciousness does not involve the existence of a single central self.
Dennett, instead, argues that the mind is occupied by several parallel "drafts". A "draft" can be roughly viewed as a narrative that occurs in the mind, and that is typically triggered by some interaction with the environment. At every point in time, one of those narratives is dominant in the brain, and that is what we are conscious of. "Consciousness" is a vague term, which simply refers to the feeling of the overall brain activity. But the truth is that there are many drafts, all working in parallel. There are several narratives in the mind going on at the same time.
Dennett is opposed to the idea that there is an enduring mind because it would imply that there is a place in the brain where that mind resides. He thinks that such "Cartesian theater" is absurd and that the mind is implemented by multiple parallel drafts.
A mental content becomes conscious by winning the competition with other mental contents and therefore lasting longer in the mind. A mind is an organization of competing mental events.
Despite the apparent continuity of our experience, consciousness does not flow at all. There is no single stream of consciousness a` la William James because there is no "Cartesian theater", no central control. There are parallel circuits, which produce parallel drafts of narratives. The continuity of consciousness is an illusion.
Consciousness doesn't even exist all the time, as "probing precipitates narratives": people are not always conscious of what is happening to them until, for example, somebody else asks them about it.
Dennett also believes that the goal of those drafts, the goal of the mind, is truly to manage "memes". The mind was created, evolutionary speaking, when memes "invaded" the brain. The mind of each individual is created little by little as memes invade it. The brain has become a computer that collects memes. The mind is a machine to process memes, not too different from the body, the machine that processes genes. Consciousness is but a collection of memes.
The British psychologist Susan Blackmore has expressed the same view in more radical words. The conscious self is but a story built by memes. In this sense, it makes no sense to talk of free will. Free will is the consequence of the story (the very complex story due to many interacting memes) that is playing in the brain.
Dennett views religions and ideologies as memes that spread from mind to mind. These memes created our consciousness by degrees (mildly put, they had a tremendous influence on our thinking). Memes such as religions were originally ideas that sprung into somebody's mind. Jesus' meme, for example, was that all humans are alike: you are like me, regardless of your name, tribe or country. Each meme like this creates a new degree of consciousness. Around the world religions and ideologies made people think and become aware of the others, of death, of the world. They are contagious: once somebody talks to you about everlasting life, you can't stop wondering about it and will tell someone else. Each religion introduced minds to novel ideas about the world. Before the birth of science and ideology, religion was the main way in which minds kept expanding their consciousness.
Ultimately, thinking is processing of memes: our "mind" is the process of absorbing, understanding, adapting and broadcasting memes.
People tell us what to think and we think their thoughts. What we think are other people's thoughts. Are any of our thoughts "ours"? Or are we only vehicles for thoughts to spread from mind to mind?
However, one could argue that the "reproduction" of a meme is often not conscious (e.g., when I start whistling a song that I heard on the radio). After all, i am truly conscious only when I rid myself of memes. Then I can focus on what is truly "me". Consciousness is a failure of memes: the more powerful the memes the less conscious your mind. And, conversely, the more conscious your mind the less powerful the memes that try to invade it.
These ideas all point in the same direction, towards a Darwinian picture of consciousness.
The USA neurophysiologist William Calvin has put forth a theory called "mental Darwinism" that neatly abstracts this view.
Just like the immune system and the evolution of species are driven by natural selection, mental life too is driven by natural selection. A Darwinian process in the brain finds the best thought from the many that are produced continuously. Thoughts evolve subconsciously. As Carl Jung said, dreaming occurs all the time but we can't see them when we are awake.
Calvin's emphasis is on movement: ultimately, what we think is for the sake of action. We need to move in the world and the mind is one tool to determine the most efficient way to do that. Far from being merely combinations of sensations and memories, thoughts are movements that haven't happened yet.
To explain how this works, Calvin has introduced the concept of a "cerebral code". Cerebral code is the equivalent of the genetic code: it allows for reproduction and selection of thoughts. A cerebral code copies itself repeatedly around a region of the brain, in a manner similar to Donald Hebb's cell assemblies. Thought arises from the copying and competition of cerebral codes. Our actual thought is simply the dominant pattern in the copying competition. The brain is an evolutionary system. The brain is what Calvin calls a "Darwin Machine".
He has shown that circuits in the cerebral cortex act as copying machines, but they copy in a Darwinian fashion, introducing mistakes that continuously create variants. Such variants then compete for cortex space. Calvin claims to have found in the brain all Darwinian algorithms for evolution, and even the catalysts that speed up evolution, i.e. the equivalents of sex, island settings and climate change.
Based on the fact that brain lesions remove consciousness only when they remove performance, in 1988 the USA psychologist Marcel Kinsbourne reached the conclusion that consciousness "is" performance, and developed an "integrated cortical field theory" of consciousness.
Kinsbourne criticizes the idea that consciousness sits at the top of a pyramid of cognitive faculties and that it is produced by the neural activity of a specialized region of the brain.
Kinsbourne believes that consciousness is not a product of neural activity: it is the neural activity itself. The brain does not generate consciousness: it is conscious. There is no need for a special region to manufacture consciousness. Kinsbourne criticizes the idea that for some information to become conscious it has to be input to a special region of the brain, which is in charge of "transducing" neural activity into a conscious feeling. Kinsbourne believes that it is not the region that matters but the state of the circuit. Any region of the brain can be conscious when its circuits are in the appropriate state.
There is no central site for consciousness: any site can host consciousness. In this model there is no need for binding. And the model admits the possibility of more than one consciousness. Kinsbourne's model is "heterarchical", i.e. highly distributed.
The USA neuroscientist Denise Ingebo-Barth believes that consciousness is a stream of discrete conscious events, just like a film is made by a stream of frames. The nervous system operates based on its own programming and its input. An operation of the nervous system results in a "trajectory" of neural events in the brain. Whenever that trajectory crosses the thalamus, a conscious event is generated. That trajectory could be coming from the senses (and result in a sensation) or the cortex (and result in a thought) and could be going to the cortex (and result in a memory). Trajectories evolve through a series of possible "fluctuations" and superimpositions, and, when they cross the thalamus, result in feelings.
The Dream of Consciousness
Scientists who studied dreams, such as Jonathan Winson and Allan Hobson, ended up believing that dreams hold the secret to consciousness, and that consciousness may simply be a consequence or manifestation of the same process that creates dreams.
Winson believes that the "subconscious" is an ancient mechanism involving REM sleep, according to which memories and strategies were formed. Dreams were helping us survive a long time before our mind was capable of providing any help at all. The mind could then be but an evolution of dreaming. First the brain started dreaming, then dreams took over the brain and became the mind. Maybe the mind is simply one long, continuous dream of the universe.
This account of how the mind came to be is similar to the hypothesis that the mind was created by memes. Dreams and memes share the property of "invading" the mind, although one is private and one is public (as Joseph Campbell's aphorism goes, "a myth is a public dream, a dream is a private myth").
Hobson's theory of dreams focused on identifying the two chemical systems inside the brain that regulate the waking and the dreaming experience (the "aminergic" and the "cholinergic" systems). Hobson came to believe that the interplay of these chemical processes is responsible for all of consciousness.
Conscious states fluctuate continuously between waking and dreaming. Even at the extremes, both chemical systems are active. Between the extremes there is a continuum of states which explains phenomena such as hypnosis, fantasy, concentration, etc. The three fundamental states of consciousness are waking, sleeping and dreaming. Hobson's model of AIM (Activation/ Information/ Mode) attempts to identify the quantities that regulate the transition from one state to another.
According to Hobson, mind is more than consciousness (parts of it are unconscious) and dreams are part of consciousness.
Consciousness is a graded characteristic.
"Mind" is all the information in the brain. Consciousness is the brain's awareness of some of that information.
Ultimately, consciousness is the brain's representation of the world, the body and the self. Consciousness is a representation by the brain of the representation by the brain of the world, the body and the self. Adult humans possess the brain circuitry to achieve this "representation of a representation". That circuitry constitutes a "secondary" network within the brain that is responsible for "meta-representational" functions.
A lot of what "consciousness" is depends on time. But time is the ever elusive quantity. The Hungarian philosopher Julius Fraser is among those who think that we use the same word, "time", for different things. Fraser has resurrected the concept of "umwelts" (a term originally introduced by Jacob von Uexkull to refer to each species' unique experience of the world) and applied it to different levels of organization of Nature. At each level the world appears in a different light.
At the lowest level of organization, the level of pure energy, time does not exist: the lowest level is atemporal.
At the quantum level (the level studied by Quantum Physics), reality oscillates between waves and particles, which means that time oscillates between existence and non-existence: the quantum level is prototemporal. At this level causality is stochastic.
At the chemical level, there is time, and it is the time of classical Physics, the time that we can measure and that is absolute. Classical Physics can be played in either direction, so time has no preferred direction: the classical level is eotemporal. At this level causality is deterministic. There is no "now".
At the biological level, time assumes a specific direction: one can only go forward (live and die), never backwards. And "now" is a fundamental concept. The biological level is biotemporal. At this level causality is emergent.
At the conscious level, the forward direction is even stronger, because we can even experience time before we existed and after we will cease to exist. The conscious level is nootemporal.
Human time contains all of these forms of "time". Human time is a recapitulation of the evolution of consciousness through all those levels.
The Deception of Consciousness
The Danish mathematician Tor Norretranders pointed out that the mind is more than what we feel.
The senses process huge amount of information, but consciousness contains almost no information at all. Most "mental" life never becomes conscious: it is lost in the processing. Large quantities of information are discarded before consciousness occurs. The discarded information, nonetheless, has an influence on our behavior. There is a non-conscious aspect of the human experience that we are not familiar with because we cannot "feel" it.
But this also means that consciousness is mostly about what happens inside us, not what happens outside. Sense data are processed according to our brain structure and matched with data in memory, and processed again, and then a conscious feeling arises. Very little of the original sense data is present when the feeling arises.
Sense data are filtered by countless neural processes in the brain before they become conscious sensations: we cannot experience the sense data, the original. We can only experience the finished product, never the raw material. We only experience a bit of what our body experiences and even that "bit" is not exactly what the body experienced but a "doctored" version of it.
The paradox is that our brain knows more than our consciousness does.
There is self-deception on the part of consciousness: before we experience it, the content of consciousness has been processed and transformed from its original format. Consciousness presents us with an altered, subjective, tampered with, view of reality but doesn't tell us so.
Norretranders separates the conscious (thinking) "I" from the acting (instinctive) "me". The "I" is held responsible for the actions of the "me", although the "I" is often not aware (literally) of what the "me" is doing.
If Lyss Margulis' theory of evolution through endosymbiosis is true, than each "me" is made of other "me's" (each data-processing organism is made of data-processing organisms).
And then one can also imagine that all "me"'s are part of the mother of all "me"'s: Gaia.
Personality and the Darwinian Mind
The same process that accounts for the origin of species is probably responsible for the origin of thoughts. Just like species spawn more species and generate a branch of the tree of life, so thoughts generate threads of thoughts. Threads of thoughts may get weaker and weaker until they disappear, or they may get stronger and stronger. It all depends on experience. But at any time, the mind is full of competing threads.
The "mind", just like the brain, obeys laws that are Darwinian in nature. Both the mind (the system of thoughts) and the brain (the system of neural connections) obey the same laws of variation, selection and evolution that apply to species and to antibodies. Both neural structures and thoughts vary in a "random" way and are selected by the environment.
Thus "personality" may just be the result of natural selection of thought threads. Whatever threads are reinforced by the experience of an individual constitute the personality of that individual.
Degrees of Consciousness
There is a level of consciousness that we do not achieve all the time, and some people may never or rarely achieve. Teenagers tend to watch movies and wear clothes and even eat food depending on which message prevails in marketing campaigns. The kids who do not follow the "trend" are considered "freaks", "weirdos". The truth is that the weird kids are probably more conscious than their friends. The weird kids are probably the ones who realize that there is nothing special about that actor or that fast-food chain: it is just that a lot of money has been spent to promote them.
As people grow up they tend to be more aware of why they do things. Some keep following the trends while others become more and more individualistic. The latter are invariably labeled as "eccentric": "eccentric" means that you use your brain instead of letting an external phenomenon condition your brain. The more "conscious" you are, the more eccentric they think you are.
The Beatles, Hollywood stars, Coca Cola and McDonald’s are all examples of things that people like because they have been told to like them. The less conscious somebody is, the more dependent that person will become on those things.
Society is built on a careful balance of thinkers and non-thinkers. Society relies on a few thinkers to break the rules and bring innovation, but at the same time relies on non-thinkers to perform the daily tasks that keep society alive. Business relies on a few people to bring innovation and on millions of non-thinkers to buy it. Capitalism, communism, fascism all rely on people not to think too much, otherwise the system would become highly unstable.
If people thought more, McDonald’s and Coca Cola would be out of business, and only a minority would listen to pop stars or watch Hollywood blockbusters. And probably very few people would work as hard as they do. It would be total anarchy.
Not only there exist different levels of consciousness, but society (and possibly nature at large) depends on a delicate balance of those levels. A successful society is made possible by the very fact that its members have different degrees of consciousness.
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