BIOLOGY OF MIND COURSE INTRODUCTION
THINKING ABOUT THINKING
-So, what's the point of a lecture on `thinking about thinking' why don't we just cut to the chase, get to the meat and potatoes, and talk biology and brains.
-Well...the problem is, I'm speaking words, and you're listening to them - using this thing we call an "I" or a "self". Maybe it wouldn't be a bad idea to try to get a grip on what we are trying to explain in the first place.
-We need to discuss up front how we use words to attempt descriptions of selves, minds, and consciousness before we proceed to bootstap back to understanding how conscious minds might have appeared during the evolution of life on this planet and how they generate a self as each of us grows from an infant to an adult.
-I'm going to go through a number of assertions or debating points, trusting you have read Chapter 1 of the text, because most of what I'm saying supplements that.
The text, and much of what you will be hearing in this course make an implicit assumption, that mind and body are the same thing.
-The point, or assertion, is that we are made of the stuff of atoms and molecules, and even the most rich of our emotional and social experiences rise from forces as impersonal as the birth and death of stars. My own feeling is that this is not a arid or nihilistic or soul less perspective, on the contrary that understanding it can enhance and deepen our experience of being human. But, this perspective, understandably, upsets many people.
Rene Descartes' famous formulation "cogito ergo sum," i.e., "I think therefore I am" posited a clear dividing line between the mind and the brain. The mind left to spirit and the church, the brain and the body left to science
One of the messages of this course is going to be that in fact the cathedrals of our intellect are infused by the inborn emotional wiring of our reptilian brain stem and also the distinctive emotional features of our early mammalian brain which regulate affiliative, social, and bonding behaviors.
It is a challenge to realize that Descartes got it just backwards, and that "I am, therefore I think" is a more appropriate statement than his famous quotation, "I think, therefore I am." It is much better to be informed of the ways in which our reason can be distorted as well as enhanced by our emotions than to be deluded into imagining that we can face the problems of the world in a truly objective way.
The depth to which this idea has permeated our culture can be seen in the way we construct ourselves. Let me ask you glance at this sentence, and then look away while you repeat it to yourself:
`I have a brain.'
Now, look away while you think or speak:
`This brain has itself.'
Does repeating these phrases feel the same to you?
My guess is that the first statement feels comfortable to you while the second feels a bit more alien, even though as far as we know they are saying the same thing. Thinking "I have a brain" corresponds to our daily experience of a narrative self, a little person or "I" inside our heads, distinct from our body, always seeing and commenting on what is going on. Do you think of this "I" and your brain/body as two distinct things?
Let me ask for a show of hands, how many of you think there is something special about mind that can't be explained in physical terms, how many think mind is physical, how many abstain, or aren't sure?
If your answer is yes, you are a dualist of some sort. You take issue with the materialism of modern science which argues that mind is the sum of the physical components of the brain - its ions, molecules, and cells and their activities. However, if the self or "I" is different from the stuff of the brain what is it? Is it some special kind of mindstuff or essence distinct from the physical matter of which you are composed?
Like the ectoplasm of victorian seances? or the slime of the Ghostbusters movies?
Dualists have the problem of explaining how mind, as a non-physical entity having no mass or energy, could interact with the physical stuff of the brain.
Thinking that you are just the physical stuff of your brain and that a "chemistry of consciousness" specifies your behavior probably doesn't feel quite right to you. But, consider how profoundly your mood can be altered by just a bit of coffee or alcohol.
Consider the numerous cases in the psychiatric literature of people who, with no previous history of mental illness, became psychotic, and were miraculously cured when a bacterial infection of their cerebrospinal fluid was diagnosed and antibiotics applied.
Where does the body stop and the mind start in these cases? It makes more sense to think of them as a unit. Chemistry can alter our behavior, and our behavior can alter our chemistry.
As an example of the latter, remember a time when you have moved quickly to avoid an oncoming danger, and then remained excited for a period as adrenaline continued to pump into your bloodstream.
Now, while this course is taught from a scientific viewpoint that emphasizes the unity of the physical mind, body, and environment, it makes no comments about the spiritual traditions that some of you choose to follow, and in fact some of the most creative essays I've read in previous years of this course were written by deeply religious students trying to square their religious beliefs with what we known about biological evolution, or how the mind works.
Let me move on now to add another point:
A further point is that our distinctively human intelligence, that spins stories using language, is a very thin veneer over a vast animal undermind amazing similar to the minds of our closest animal relatives such as the chimpanzees, who show social and moral behaviors very similar to our own, and who share 98% of our genes.
You've seen all the drawing of the so called ascent of humans, actually this is a vast oversimplification, as I'll be telling you later.
We have vastly more in common with higher mammals than most people are willing to admit, a social and emotional substrate over which our language is overlaid. We can feel such solace and companionship from our pets because some of their external behaviors seem so similar to our own (affection, fear, anger, sadness), and we feel that they must be having internal experiences similar to ours.
Still, as you will be seeing when I talk about evolution and animal minds, a real chasm appears to separate our minds from the minds of animals, who exist only in a world of the present, and who, even thought they can perform feats of memory, do not know `know that they know'. There is utterly no evidence that any animals can use the scaffold of language to reflect on past and future, to have a self conscious history.
-Most animal minds show evidence only of an episodic intelligence, living on cusp of the present, looking into events, not reflecting back on them, accessing memory as guide to action, but not necessarily in a human style self conscious way. A quote from John McCrones's book "Going Inside": "animals do not see into a moment, rather they look out from it. Subjectively, the animal brain would always be facing forward, focused not on where the latest shift in viewpoint has come from, but where it is heading. Rather than feeling liked an observer or a passenger, and animal would have a feeling of simply being the vehicle, of doing the journey. This suggests that even our feeling of being there during a moment, observing, supervising, and taking decisions, is a habit grafted onto consciousness."
-Antonio Damasio has suggested an intriguing model for how our minds are built on animal minds...for having a self with sense of ownership,
-core consciousness, core self having a present centered self, a past only of many seconds of working memory, having sense of ownership of a self, lesions studies: brain stem, thalamus, limbic, and other medial structures associated with core self. Great gobs of neocortex can be removed with compromising this. This would be the main part of the present centered animal mind.
-extended consciousness, extended self, having a visual or linguistic narrative history of that self and its possible futures. Requiring neocortex, specific aspects, visual, linguistic, auditory etc. blasted by brain lesions to specific parts without compromising core consciousness.
-Does a human style self that has a recall of its history and think about its future happen only with language. This is a tough one, and I vacillate back and forth on it at least once a month. ...basically I don't want to go there, except to mention some options.
-one extreme model is that there is no human style self in the absence of the human interactions, verbal and nonverbal communications, with caretakers or peers on which language is built. So that without human communication you don't imagine a past and a future. The invention of articulate, grammar-driven speech as also being the invention of articulate, logic-driven thought.
-the other view says horse feathers, why can't a chimp's mind look at, play tapes of past experiences recalling visual images and sound, as a usual trick in planning and predicting futures, and why can't it image those futures, but give us not a glimmer of evidence that it is doing this... Why should it?
- When we talk about evolution of animal minds, we'll get more into the issue of, first, having a self conscious self, and second, attributing selves or mind contents to others, called having theory of mind
The next point to add is that:
MIND IS SOCIAL
-Our minds and brains, along with those of other social mammals, are irreducably social, they simply don't grow and form in the absence of close affiliative bonding between infant, caretaker, and peers during the growth and development of the brain. Our language structures have a very primitive beginning in this social world of the newborn human - with emotion laden sounds, gestures, and physical contacts exchanging meaning with caretakers long before formal language communication appears.
There needs then to be a language of gestures and sounds preceding grammar and syntax. It is from these social origins that our individual cognition, sense of self, an "I", and ability to use words and sentences grow - words and sentences whose management and understanding are the province of linguists and philosophers.
There are virtually no acts of sensing or acting that are not influenced by this social personal history of habits, of how we have grown up to make sense of the world and others. You've probably heard of people with brain damage from strokes or physical trauma who loose some specific capability, such as vision in a part of the visual world, hearing, or moving a part of the body (see the brain drawing above for these regions). There are also brain regions which, when damaged, profoundly alter our social behavior or our sense of self and others. Our sense of self and others is a very labile construct. (examples of absence seizures, anosognosia, prosopagnosia, Phineas Gage)
In this course we'll be talking about the cubbyholes that cognitive neuroscientists have put our minds into: sensing, acting, emoting, thinking, with the sometime unspoken assumption that these are discrete computational modules, like computer parts that we can speak of using engineering and scientific terms, that almost spring from nowhere.
NONE OF THIS HAPPENS, none of these tidy modules, unless we are born into a social environment in which we are held, touched, spoken to, with emotional bonds of communication, lacking this we die, as studies in orphanages have shown. Tidy engineering metaphors of modules, input, output, analysis, and sometimes misses the point that what we see and do can be fundamentally biased or skewed by this social context. It's important in studying the brain to not just look at what is before you right now, how a brain is working at the moment, without concern for it evolutionary history or its developmental history, how it grew to be the was it is.
-A next point to add is that mind is embodied.
I'm putting this on my list of points because it is an important one. While we of course will be emphasizing the brain in this course, we can't think of it like an isolated brain in a vat. The definition and boundaries of mind are fuzzy, it grows in such a tight coupling and feedback with body and with environment that it faces the circular paradox illustrated by the famous Escher drawing of two hands, which is drawing the other?
Another point to add is that MIND IS A MARTIAN:
-This is a flippant way to trying to make the point that what is really going on in our heads is vastly alien to our self experience and commonsense descriptions. Our consciousness is a very dynamic process that cannot be reduced to the activities of a few consciousness nerve cells or consciousness centers....
Who, what, is watching inside if I ask you to recall how the Mona Lisa looks? What is this consciousness or mind-stuff?
We all experience a little "I" inside our heads looking out, rather like these creatures from the movie aliens
Perhaps you can imagine the "I" in your head as actually corresponding to an array of purposeful little agents scrambling around inside, some watching the movie screen of what is going on the outside world, others operating the levers on the control panels that direct our movements.
But, either saying there is a single or that there are multiple I's inside the head just takes the problem back another step, like opening the Russian wooden doll toy that has another doll nested inside. Opening that doll, you find the next.
The hunt for purposeful agents somewhere down in there becomes fruitless. As we look further inside the brain we become increasingly convinced that there doesn't appear to be anyone at home. We don't find a specific place where there is a thinker or a feeler or an actor. Rather, there are billions and billions of nerve cells wired together in complex arrays.
Here we have to get back to language, how our language habits are influencing how we define what out there, and what inside, how we define minds and consciousness?
The linguists tell us that the variety of tricks we use to cobble together our descriptions of what we take to be our reality (metaphor, common sense folk psychology) can significantly bias and compromise our understanding, and philosophers tell us to worry about whether consciousness and be defined or explained in the first place. This is not the place for an extended discussion of these issues, but we should make a few points.
A particular human culture is distinguished by the words, rules, and categories that it has grown. Simple facts about the social and physical world, things that "anyone can see," are taken for granted. Anthropologists working in remote areas often have to endure being laughed at because they don't know the obvious. Only a child or a fool would not know that a man must not enter a hut in which one of his male relatives has died, or that it is dangerous to venture out on the night of a new moon. Experiences that confirm with these rules are taken as evidence for it, but if a man who goes out in the full moon and is not harmed, it is explained away, perhaps a shaman walked on that path the day before, or he had a protective charm. We use a number of tricks to reinforce our habit of looking for what we already expect to see.This is sometimes called the `documentary method' by ethnomethodologists.
Looking for what we already expect to see is pervasive. We do this with each other, teachers frequently early on decide that some students are bright, independent, or perhaps immature and these categories then can persist in spite of evidence that might accumulate to the contrary. A test failure of a designated `bright' student is explained as their having had a bad day, while the same failure confirms the diagnosis of a slow student.
These examples may seem kind of silly, we think we wouldn't be fooled by them, yet we follow very similar procedures when we invoke categories of "mental" entities such as "emotion," "willpower," or "reasoning" because they have become categories that are publicly subscribed to performances and narratives. But this does not mean that these categories actually occur in the physical world as a definable set of physical properties. It is extremely difficult to disentangle the everyday language of reasons and assumed mental states from the language of natural science which might explain, for example, how our brains evolved to engage in conversation in the first place.
Suppose we were to transport a modern neuroscientist with a brain scanner to the period of the early Renaissance in Europe. Would not the obvious experiment be to look for the neural basis of "godly behavior." You have to ask how our current use of the word "emotional behavior" different?
For example, if we attempt to look in the brain for changes that might underlie emotions, or more specifically the emotion of fear, we find very rapidly that the behaviors associated with these semantic categories do not correlate with clearly defined brain processes. Many instances of fear correlate with activation of a brain region called the amygdala, but then there are also kinds of fear that do not appear to require the amygdala or its activation. Probing more deeply it becomes more difficult to argue for a clear qualitative difference in the brain between our viewing a neural scene and reflecting on it and of the approach of a frightening person - other than the intensity of our physical response, perhaps the extent of the brain areas activated, or the tendencies to action that occur.
This course has an organized lectures which chunks the topics we need to cover into faintly logical divisions. We have to do this because our linear serial thinking specializes in taking on one thing at a time. Thus we make separate compartments for discussing the machineries of sensation, action, emotions, social interactions. The subtle problem is that we begin to assume that these chunks actually occur in the brain, rather than possibly being an artifact of the linguistic processes we humans have developed to exchange information about them.
One process that can bias our insights, frequently outside our awareness, is the use of metaphors (words for one object or idea being used for another to suggest a similarity between them, but without an explicit comparison). In our common sense, documentary method, or folk, psychology we often describe our mental states and processes using metaphors. Someone saying to you "I don't want to put ideas in your head" is taking mind to be a container. If you say "Part of me doesn't want to do that" you are using the metaphor of mind parts as persons. "John saw that Jim could not be trusted" is making believing like seeing. This sort of process is pervasive in our lives. As another example, consider how the fundamental physical verticality schema of up and down - relevant to any animal moving against gravity - is usually metaphorically projected to a whole array of oppositions: happy is up, sad is down; health is up, sickness is down, rational is up, emotional is down. When we come to the business of trying describe minds we must realize then that the dice have already been loaded, that a vast array implicit assumptions may already have influenced us.
Now, returning to my final point that the `mind is a martian' I want to tell you about a few simple experiments that show how spooky the downstairs of our consciousness is, how there is alien or martian feeling stuff going on very different from what our self conscious narrative "I" thinks is happening.
This involves movement, initiating actions.
-In a well known experiment by Benjamin Libet the subject is instructed: "Flex your finger to push the button when you feel like it, and tell us where the hand on the rapidly moving clock is when you decide to do that." The time at which an EEG signal indicating brain activation for movement occurs is set as zero time, the report of awareness of intention to push the button is about 350 msec (0.35 seconds) later, and the actual EKG, the voltage in the finger muscle doing the push, happens about 200 msec later than that.
We are 'late for consciousness', the action had already started. The brain has started on our acting earlier than our consciousness of it.
-What's the point of this delay....What's the point of our even being conscious if everything is ready to go before we know about it. We do become aware before it happens and can veto it. Most of the time it is OK and to be efficient we really ought to get going with it fast and now wait for consciousness, but it case the movement ought to be suppressed, like socking someone, we can inhibit it at the last minute.
-By the time we are aware of willing a movement it is well under way, but we get to cancel or edit it.
It may be that we, that is, our conscious selves, don't so much have 'free will', as we do 'free won't.' This consciousness is important because it lets us plan novel responses, to model and survey options for actions to preserve ourselves, in a way that automatic routines never can...
-Have we abolished "free will" ..... in a deeper way, no.....
-The point is that the consequences of my action are programmed back into the next automatic startup of the next action as an anticipation. We actually function in a find of extended present. Professional athletes do better, as in returning a tennis serve, not because their reaction times are any faster, but because their trained anticipation machinery can usually accurately guess from the initial arm movements of an opponents serve way before the ball is hit, where the ball is going to end up, and start preparing their response then.
-" Anticipation hold the answer...... predictions ease our passage into the moment. In some sense we are conscious ahead of time. We do not notice the large gaps (.1, .2 sec.) in our awareness because our brains move seamlessly from a state of intelligent forecast to a state of confirmed sensory expectation.
So, I've basically made two points about acting...
Now, let me give you one more example of how our brains are doing something we are usually unaware of during our experience of sensing the external world.....
-Here the instruction is to push the button in response to a light coming on. The button push occurs about 200 msec after the light comes on. If the instruction is: "slow down your response by the tiniest possible amount," then approximately 700 msec passes before the button push. There is a quantum jump of 500 msec, waiting for consciousness to develop if a conscious rather than unconscious response is requested.
-Again, what's the point of this half second. There is another one, our unconscious undermind can shape what we think we are seeing out there in the real world.
-This undermind knows the history of our development, our learning to sense and name things, the ace of spades is black, the ace of hearts is red, if someone flashes a red ace of spade in front of you your are more likely to see one of the two choice you are already familiar with. We compare the information that comes with our library of images, and frequently assume that the stored image is the correct one.
-This delay required for consciousness can do some very spooky things, making us suppress awareness of things that are there, or make us think we see things that really aren't there. We do rather major unconscious editing of what comes in before we are willing to be consciousness of it. There is a vast basement or undermind working on which our conscious thoughts are an overlay.
So, to add to what I said about acting:
-Our consciousness is sort of an after the fact news flash of what our evolved mind thinks it relevant for us to know. It is a product of our brain operations, not a source.
-Why did this machinery work out this way....why did animal brains, cumulating in ours, evolve these mechanisms... for efficiency...most of what we do is on autopilot we consciously attend to what is or might become an issue or problem.
-Automatic sensing and acting autopilot, automatic car driving example, undermind keeping a continual check and giving 'news flash' if something unexpected or dangerous appears which should suspend the automatic pilot.
-While this autopilot can be useful, it can also be the equivalent of falling into mental ruts, with the brain using familiar routines, essentially not giving the brain much new exercise. One of the things that recent research is showing is that the brain is literally enlivened by encountering novelty, or by turning off the autopilot to perceive familiar things in different ways, blood circulation is increased, modulating molecules that enhance arousal and attention are released, we're learning that the brain is continually manufacturing new nerve cells, possibly for use in laying down new memories or skill pathways.
Now I want to turn briefly to our emotional minds, our emotional brain constitutes our value giving machinery, going back to that picture of the brain I showed earlier, the 'what's it to me' decision between sensing and acting.
-think of the number of times you have looked at the face of a stranger and instantly liked or disliked them. Why is this? Sometimes, if you stop to think about it, can you can recall a similar face from your childhood that you either avoided or approached, stored in your unconscious memory and influencing your reactions to similar faces you now encounter.
-we attach an emotional tag, or valence, to almost everything we perceive, even sounds, as in nonsense words, that have no meaning... those with more vowels, like lamujuva are slightly pleasing, some with more consonants, like rakachaka, are faintly unpleasant.
-We have a Manichean undermind, like the Persian religious sect of the 3rd century, that divides most aspects of the world into either good or evil, our brains persist, usually beneath our conscious awareness, in putting a good or bad label of what we sense, is it something to go for or avoid.
-the emotional filters that derive from our development are a distinct brain system of memories, but apart from our explicit memory, knowing about, recall. Some patients with damage to the hippocampus (a brain structure important in forming explicit memories of events) cannot remember anyone they meet, but they begin, without knowing why, to avoid caretakers that are unpleasant to them and to approach caretakers that are friendly and open. That emotional memory requires another small part of the brain called the amygdala, and interestingly, patients with damage to this amygdala but an intact hippocampus, can sometimes remember the objective facts about a situation, but not the emotional reaction that went with it.
-Some very elegant experiments by LeDoux and others have shown that emotional reactions can be mediated brain circuits that are different from our self conscious "thinking about" circuits, and that these emotional value circuits can act faster than our thinking brain.
-If a shadow suddenly looms in your upper right visual field, or if you see a long thin wavy shape on the ground to your right you are likely to jump aside well before you are able to consciously decide whether an object is falling on you from above, or whether the shape on the ground is a snake or a piece of rope.
-so what we end up with, in addition to our acting and sensing underminds, is an emoting undermind that can act during the 0.5 seconds it takes for consciousness to develop, it can add a negative or positive tint to our perceptions outside of our awareness.
- We can train ourselves to sense the different timing of thoughts and feelings in our brains. Because the timing and location of the brain's emotional pathways can be different from our self conscious 'thinking about' pathways, it proves possible to sometimes loosen up the habitual linkages between some of our thoughts and feelings. To exert more choice in how we feel about chronic situations.
-A more complicated sort of undermind filter is our actual self image.
-We can think of this thinking mind as a self constructor (beaver-dam, spider-web), this self construction is essentially a confabulation whose accuracy must continually been updated, and we see interesting evidence for such a confabulator in cases where it can go awry.
-For example, some stroke patients with damage to the right parietal lobe a condition called anosognosia, will deny the existence of the left side of their body "Oh, that's not my leg, it must belong to someone else."
- The idea is that the language centers in our left brain, which is not damaged, is making up the best cover story it can to preserve the sense of an intact self. There is evidence actually that the left hemisphere generates the story line, and the right hemisphere checks it out. When the right hemisphere checking mechanism is disabled by a stroke, the left hemisphere just wings it, patching together whatever cover story is needed to preserve its sense of a self.
-The self system acts as yet another sort of undermind, in parallel to the acting, sensing, and emoting underminds I touched on so far.
-This self system, always testing what might be threatening, set the threshold at which we are willing to let information entering our conscious awareness.
-One simple experiment is to flash word with increasing duration until identified, neutral words (Cat) named much sooner than threatening words (Death) => recognition and K are NOT the same thing. Threatening word is recognized, self-defense system raises the upper threshold to keep it out of consciousness
-This self system sets how willing we are to rely on delicate hunches, or dubious or unconscious information.
-another simple experiment shows this, access to information (for example, being able to recall previously shown pictures) improved if subjects feel 'safe' as in "just enjoy guessing, this isn't part of a test" or, "which scene do you prefer" (rather than recognize).
-When self esteem is at stake (test, trial) delicate or unconscious information seems to be disabled or dismissed.
So, these have been some examples of the vast undermind that lies under our sense of an "I" , our acting, sensing, feeling, and thinking.....a whole set of filters that act during the roughly half second that our brains can be processing stuff before it enters our consciousness, a rich undermind of acting/sensing/emoting/thinking on top of which our consciousness awareness is a thin veneer.
Through this course you're going to getting many perspectives on how this all comes to be.
Let me list again the slide of the points I've been building, and point you to an article you might find useful if you do an essay on some of the topics I've touched on.
"I am John's Brain" Andy Clark
Journal of Consciousness Studies, Vol. 2, pp. 144-8, 1995
http://www.zynet.co.uk/imprint/online/Clark.html
The best idea seems to be that the brain isn't like a classical top-down corporation or a computer run by a master central processor. Our consciousness is mechanically implemented by a process more analogous to an economy or a political party, a distributed system without much central authority.
It's more like a chamber music group than an orchestra in which everyone strictly follows the conductor. There is no central place from which a puppet master pulls all the strings.
Our brains are a collection of linked subsystems each of which specializes in specific kinds of jobs. They are not general purpose problem solvers using the same distributed common processes for all tasks. They are more like a Swiss army knife that has special gadgets for different tasks.
Large computational problems (vision, audition, movement, language generation) are split into a collection of parts processed by specific brain regions. These parts can be revealed when they are damaged by brain lesions or genetic mutations. They can sometimes be directly visualized in living brains using imaging techniques or electrical recordings.
The specialized modules are not isolated but interact extensively with each other. One of the best known examples of this is the different areas of the brain that process different aspects of a visual image such as form, motion, distance, and color.
The central emphasis is that we are a society of mind, built up of a hierarchy of agents, simpletons, stable subassemblies, multiple drafts, or component selves. (The words vary more than the ideas.) Our parts interact with each other like players in a symphony orchestra, with both vertical organization (following a director) and horizontal (adjusting playing as other players are heard).
The modules are not what an engineer starting from scratch would have designed (supposing there were an engineer who could design a brain), but rather a hodgepodge of evolutionary adaptations piled one on top of the other, with some components possibly duplicated and adopted for uses and tricks quite different from their original purpose.
Just as we are stuck with the QWERTY keyboard, designed in 1872 to avoid jamming of type bars that vanished long ago, so the modern brain makes do with modules designed to solve ancient problems.
Consciousness is what natural selection has given us to have thoughts that would, most likely, help us survive in the world of our ancestors, not necessarily thoughts that are consistent or true.
One of the goals of this course is to sketch out the many components of our perceiving, acting, emotional, linguistic, etc. minds that make us a society of mind. How they evolved, how they develop. I think you're going to enjoy it.
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