My first experience with the left/right divide was a one-day course "Drawing on the Right Side of the Brain" at SIGCHI 98(?). Based on her book and a longer course, it was the first time Betty Edwards had tried to condense her originally multi-week course to a single day. It worked for me.
During the course she referred repeatedly to L-brain and R-brain as metaphors because at the time medicine and psychology were busy denigrating any reality of left/right brain differences and she had clearly been beaten up by the "experts". I haven't talked to her since then, but I'm sure the last decade's real research on the differences has gratified her.
There were two exercises that made an impression. I hadn't read the book before the course, and came into the class doubtful that I could learn to draw. The exercises had a profound impact on me. I was able to draw, and I felt the mental shifts she described as necessary to do it. I will briefly describe them here.
The first exercise was to copy Picasso's "Portrait of Igor Stravinsky". I have tried to copy other images in my life, so I was quite aware of my inadequacies in doing so. The second exercise was to draw my hand, and I also doubted that I could do that. But I was open to learning.
The trick is to copy Picasso's "Portrait" upside down so as to disengage the left brain. I started in, and was really happy with how well I was doing, both in speed and accuracy. Until I got to the hands. Without thinking about it, I watched my drawing turn to crap. I erased the crap and forced myself to look only at the individual lines. Drawing each line segment very slowly, I faithfully reproduced the hands. After that I relaxed into my previous speed and accuracy until I got to the head. I was ready that time and went into the slow, one-line-at-a-time mode and finished the head. Of course, this is all described in the book, which I looked at later.
The exercise allowed me to experience the switch between left and right hemispheres. Surprisingly, there wasn't any feeling of clumsiness in my drawing hand when the change occurred. Apparently the brain is well practiced at making the transition. One lesson was how subtle and natural the change is. A second lesson was how easy it is to induce the change once you know it can be done. The third lesson was, of course, what a dramatic difference it makes.
During the second exercise (drawing my hand), I played with the change and became comfortable with it. I became confident that I could do it in the future as need arises. I don't often draw, but the lessons I learned have benefited my work every since.
The lessons also opened me to thinking about left/right brain issues. The academic condescension that was rampant at the time in most cognitive literature kept me from reading more about it until recently. Now it seems that a corner has been turned, so I am immersing myself in the subject.
The overall lesson from the experience was that drawing is mostly seeing. Betty made the point that drawing isn't art, so learning to draw didn't mean we had become artists. She sees drawing as a basic skill that everyone should learn, like doing arithmetic or using a keyboard. This message is more subtle than you might think since many of our personal and social problems arise from not seeing clearly.
A corollary to the overall lesson is that most of us can really only draw well an actual (physical) object. Asked to draw a house, we would best draw an actual instance of a house. Asked to draw a person, we would best draw a real person. Drawing a generic house or person will usually lead to an uninteresting result. I don't know how artists draw things that are entirely in their heads.
Wednesday, March 16, 2011
Tuesday, March 15, 2011
Playing with the world
The primary activity of the left brain is deconstructing the world and using the resulting pieces to construct new worlds. This is the primary method of all human creativity. It's sounds a lot like playing with Legos, and it is, but there are crucial differences. In this post I want to describe the world of the left brain, just as I described the world of the right brain in the preceding post.
People are playful. We tend to think of playfulness as some sort of icing on the cake of humanity, but I believe it is fundamental. Not everyone is playful all the time. Nor do our histories talk much about play; they tend to concentrate on the serious business of survival and power. That may be what history is about, but day-to-day life is about play.
This is not to say everyone's life is fun or even that most people's lives are fun. Fun isn't the reason we play. The reason we play is that we have no choice; it is our nature.
One primary activity of the left brain is exploring the world. The right brain typically starts this process by moving the head and eyes so the central right visual field encompasses something interesting. The first thing that happens is that the left brain finds boundaries in the visual field and interprets the space between and outside the boundaries as pieces of the world. The left brain carries around a lot of re-presentation of previously found objects. A re-presentation is a somewhat idealized memory of a class of objects, something akin to an icon. That is, the first time the left brain sees an object it remembers it much as it was first seen. After seeing additional versions of the object, it forms a more general image of the object that both represents the object and re-presents it in slightly altered form. If a first level object is not recognized, the left brain will typically, look for boundaries in it, and continue the decomposition. For example, the first time a person sees what might be a house in the distance, the left brain identifies the roof, walls, doors, windows, etc.
Once the visual field has been decomposed into recognized pieces, the left brain will hold the pieces in relation to one another and see if the pieces can be recognized as some reconstructed whole. The left brain also carries around a lot of reconstructed wholes. Again, these are re-presentations of classes of real objects. Continuing the example, the left brain that sees the erstwhile house will discover that an object with a roof on the top and walls on the side, with windows and doors, is likely a house. If the match is sufficiently decisive, the left brain will "decide" that it is a house and start deconstructing its constituent parts, discovering how the roof, walls, windows and door are constructed. If the match isn't decisive, it may continue looking for matches to a whole and find perhaps "barn".
We can see these re-presentations by asking people to draw something that is not present. "Draw a house". Most people will draw an image of their left brain re-presentation of a house rather than a specific house. This left-brain re-presentation will typically be recognizable to others, but won't be considered particularly artistic. In fact, the drawing may be a better picture than what they carry around in their head because during the drawing we will be fixing obvious deficiencies like "shouldn't the walls and the roof meet?"
These collections of re-presented parts and wholes are the Lego-like building blocks the left brain plays with. When the left brain isn't doing anything else, it creates new things from these pieces, and some of these new things are added to the collections of wholes that might be found during some later exploration.
Note that the re-presentations aren't really stored as parts and wholes. We continually deconstruct and construct so that most parts are really constructed of smaller parts, and wholes are often constituent parts of more grandiose wholes. Thus we understand that doors are really made of molecules, atoms, nuclei, quarks, fields, etc., and are parts of a house in a great city on a planet in a solar system in a galaxy in one of many possible universes.
One form of creativity is seeing things that others don't see. This may result from a person having imagined (mentally constructed) something before others had actually seen it. Another form of creativity is making a physical representation of an imagined something that has never existed before, even if it just a little bit better than something that did.
The reality of a creation is perceived by the right brain and made an important part of our right-brain reality and that of others around us. Thus the creative process that started with the right-brain directing the visual field of the left brain to something "interesting" proceeds full circle to returning the fruits of creation to the right brain. This enables the right brain to find more "interesting" somethings to direct the left brain to play with.
Traditionally, creativity is ascribed to the right brain while I have described it as a playful partnership of both hemispheres. These observations are not really in conflict if you understand what artists and philosophers have been telling us forever: the foundation of all creativity is perceiving the world clearly. They tell us that by this they mean seeing the world without the veils that cloud our vision and distort reality. The right brain sees clearly, but few of us are brave enough to trust its view over that of the more familiar re-presentations that fill our minds. So for most of us, trusting the right brain is at once the most creative act we will perform and the basis of all further creation.
People are playful. We tend to think of playfulness as some sort of icing on the cake of humanity, but I believe it is fundamental. Not everyone is playful all the time. Nor do our histories talk much about play; they tend to concentrate on the serious business of survival and power. That may be what history is about, but day-to-day life is about play.
This is not to say everyone's life is fun or even that most people's lives are fun. Fun isn't the reason we play. The reason we play is that we have no choice; it is our nature.
One primary activity of the left brain is exploring the world. The right brain typically starts this process by moving the head and eyes so the central right visual field encompasses something interesting. The first thing that happens is that the left brain finds boundaries in the visual field and interprets the space between and outside the boundaries as pieces of the world. The left brain carries around a lot of re-presentation of previously found objects. A re-presentation is a somewhat idealized memory of a class of objects, something akin to an icon. That is, the first time the left brain sees an object it remembers it much as it was first seen. After seeing additional versions of the object, it forms a more general image of the object that both represents the object and re-presents it in slightly altered form. If a first level object is not recognized, the left brain will typically, look for boundaries in it, and continue the decomposition. For example, the first time a person sees what might be a house in the distance, the left brain identifies the roof, walls, doors, windows, etc.
Once the visual field has been decomposed into recognized pieces, the left brain will hold the pieces in relation to one another and see if the pieces can be recognized as some reconstructed whole. The left brain also carries around a lot of reconstructed wholes. Again, these are re-presentations of classes of real objects. Continuing the example, the left brain that sees the erstwhile house will discover that an object with a roof on the top and walls on the side, with windows and doors, is likely a house. If the match is sufficiently decisive, the left brain will "decide" that it is a house and start deconstructing its constituent parts, discovering how the roof, walls, windows and door are constructed. If the match isn't decisive, it may continue looking for matches to a whole and find perhaps "barn".
We can see these re-presentations by asking people to draw something that is not present. "Draw a house". Most people will draw an image of their left brain re-presentation of a house rather than a specific house. This left-brain re-presentation will typically be recognizable to others, but won't be considered particularly artistic. In fact, the drawing may be a better picture than what they carry around in their head because during the drawing we will be fixing obvious deficiencies like "shouldn't the walls and the roof meet?"
These collections of re-presented parts and wholes are the Lego-like building blocks the left brain plays with. When the left brain isn't doing anything else, it creates new things from these pieces, and some of these new things are added to the collections of wholes that might be found during some later exploration.
Note that the re-presentations aren't really stored as parts and wholes. We continually deconstruct and construct so that most parts are really constructed of smaller parts, and wholes are often constituent parts of more grandiose wholes. Thus we understand that doors are really made of molecules, atoms, nuclei, quarks, fields, etc., and are parts of a house in a great city on a planet in a solar system in a galaxy in one of many possible universes.
One form of creativity is seeing things that others don't see. This may result from a person having imagined (mentally constructed) something before others had actually seen it. Another form of creativity is making a physical representation of an imagined something that has never existed before, even if it just a little bit better than something that did.
The reality of a creation is perceived by the right brain and made an important part of our right-brain reality and that of others around us. Thus the creative process that started with the right-brain directing the visual field of the left brain to something "interesting" proceeds full circle to returning the fruits of creation to the right brain. This enables the right brain to find more "interesting" somethings to direct the left brain to play with.
Traditionally, creativity is ascribed to the right brain while I have described it as a playful partnership of both hemispheres. These observations are not really in conflict if you understand what artists and philosophers have been telling us forever: the foundation of all creativity is perceiving the world clearly. They tell us that by this they mean seeing the world without the veils that cloud our vision and distort reality. The right brain sees clearly, but few of us are brave enough to trust its view over that of the more familiar re-presentations that fill our minds. So for most of us, trusting the right brain is at once the most creative act we will perform and the basis of all further creation.
The secret world
The primary activity of the right brain is learning and using all the connections between all the elements of our world. These elements include all aspects of the natural world, all the constructions of man, all thoughts and feelings in our minds, and most importantly all the other people we interact with.
We are social animals, much more than we normally admit. The only other animals that live anywhere near as densely as we do are ants, bees, and termites, and we call them social insects. We have conflicts, personal, familial, and national, but most of the time in most places we live together, often very close together, leading productive and fulfilling lives.
That's the right brain. The right brain sees everything connected, including all the human beings it perceives. You can't escape that socialization, though you can choose not to participate at various levels. However much you choose to live apart, your life will be defined by that separation, and much of your right brain activity will be mediating that apartness.
The right brain has mirror neurons (watch this TED video: it's fascinating.) This is really a fully integrated major subsystem that runs through much of the right brain, though it is mediated in the frontal cortex. Mirror neurons allow us to fully understand what another person is doing physically. When we see another person lift her hand, the same neurons fire in our brain that fire when we lift our own hand. Likewise, when we see another person hurt her hand, the same neurons fire in our brain that fire when we hurt our own hand in the same way. (See the video for the reason we don't feel the same pain.)
VS Ramachandran calls mirror neurons "The neurons that shaped civilization". I call them the neurons that make us human. Just about every other neuronal system has an analog in other animals. So far we have only found limited mirror neuron activity in non-humans, whereas we are immersed in it.
Every second of our lives in which we are perceiving others, we are partially living their lives. Our right brains take in every nuance of position, action, and reaction that the people around us present. And they are doing the same with us.
This detailed and intimate observation allows us feed our theory of mind. Theory of mind is not a psychological theory, per se, but a theory my mind holds about the content of another's mind. I infer what the other person is thinking from the location and observed actions of the other, that is, my mind has a theory about the content of the other's mind. Because the right brain is grounded in reality, it doesn't turn the theory of mind into "fact of mind". It remains a theory, which is continually updated from further "observation". Note that "observation" here means the intimate feeling of "mirror neurons", not rational seeing and thinking about it. All unconscious in the right brain without effort, or even choice, unless we divert our eyes.
One of the most powerful aspects of mirror neurons is the observation of other people's eyes. Our right brains typically maintain a 3D picture of where we are in the world. The picture is so accurate and detailed that we can often correctly infer what another person is looking at by seeing where they are and where their eyes are pointing, even if the thing they are looking at is not visible to us. This is an incredibly complex geometric calculation that our brains can perform in real time while doing other things.
One of the most notable aspects of mirror neurons is the observation of other people's faces. Our minds express themselves richly in our faces. Such expression is very subtle, and there may be dozens of aspects of our faces that embody that expression. Our mirror neurons allow us to infer what thoughts we might have been thinking that created the exact movement of a specific facial muscle that we see on someone else's face. To the extent that we are right, we gain insight into the person we are looking at. We can also be wrong since we express ourselves somewhat differently.
The target of mirror neurons extends outside the body. When we see a car driving down the road, we not only infer the state of the car but that of the driver inside, even if we can't see the driver. And we do this for many cars all at the same time. The amount we can infer about the state of the other drivers' minds is limited, but it is sufficient to allow us to safely drive in crowded cities and freeways.
Our babies are born into the secret world. They are born with the skills to participate in it immediately. They don't recognize a boundary between self and other. There is only the secret world and all the wonders in it. Parents who bond with their babies are being re-initiated into the secret world. As the baby becomes initiated into the constructed world, learning words and concepts and proper behavior, the child is often forced to choose which world to attend to. The secret world never goes away, but most of us, parent and child alike, lose touch with it as the child grows up.
It seems to me that a pack of canines shares a similar secret world communicated (mostly) non-verbally. I don't know the exact nature of that secret world, but I suspect is similar to our own. (For example, a dog can do the same 3D positioning trick I described above.) I believe the reason dogs have been such successful human companions is that we can share some part of our secret worlds.
Whether we are walking down a crowded street or sitting at home with family, we are participating in a continual, omnidirectional communication with those around us, and the knowledge we infer from this is as real to us as any other sensory input.
The secret world is always there, but we are not often consciously aware of it. The experiences and circumstances of our lives often teach us to disconnect our consciousness from the secret world. There is a lot of emotional content shared in the secret world, and much of it is sad, and some of it is disturbing, so we learn to ignore it. There are people who can't hide from the secret world, and there are many who never experience it directly. But we all use the information from the secret world to allow us to live in (more-or-less) harmony with others.
We are social animals, much more than we normally admit. The only other animals that live anywhere near as densely as we do are ants, bees, and termites, and we call them social insects. We have conflicts, personal, familial, and national, but most of the time in most places we live together, often very close together, leading productive and fulfilling lives.
That's the right brain. The right brain sees everything connected, including all the human beings it perceives. You can't escape that socialization, though you can choose not to participate at various levels. However much you choose to live apart, your life will be defined by that separation, and much of your right brain activity will be mediating that apartness.
The right brain has mirror neurons (watch this TED video: it's fascinating.) This is really a fully integrated major subsystem that runs through much of the right brain, though it is mediated in the frontal cortex. Mirror neurons allow us to fully understand what another person is doing physically. When we see another person lift her hand, the same neurons fire in our brain that fire when we lift our own hand. Likewise, when we see another person hurt her hand, the same neurons fire in our brain that fire when we hurt our own hand in the same way. (See the video for the reason we don't feel the same pain.)
VS Ramachandran calls mirror neurons "The neurons that shaped civilization". I call them the neurons that make us human. Just about every other neuronal system has an analog in other animals. So far we have only found limited mirror neuron activity in non-humans, whereas we are immersed in it.
Every second of our lives in which we are perceiving others, we are partially living their lives. Our right brains take in every nuance of position, action, and reaction that the people around us present. And they are doing the same with us.
This detailed and intimate observation allows us feed our theory of mind. Theory of mind is not a psychological theory, per se, but a theory my mind holds about the content of another's mind. I infer what the other person is thinking from the location and observed actions of the other, that is, my mind has a theory about the content of the other's mind. Because the right brain is grounded in reality, it doesn't turn the theory of mind into "fact of mind". It remains a theory, which is continually updated from further "observation". Note that "observation" here means the intimate feeling of "mirror neurons", not rational seeing and thinking about it. All unconscious in the right brain without effort, or even choice, unless we divert our eyes.
One of the most powerful aspects of mirror neurons is the observation of other people's eyes. Our right brains typically maintain a 3D picture of where we are in the world. The picture is so accurate and detailed that we can often correctly infer what another person is looking at by seeing where they are and where their eyes are pointing, even if the thing they are looking at is not visible to us. This is an incredibly complex geometric calculation that our brains can perform in real time while doing other things.
One of the most notable aspects of mirror neurons is the observation of other people's faces. Our minds express themselves richly in our faces. Such expression is very subtle, and there may be dozens of aspects of our faces that embody that expression. Our mirror neurons allow us to infer what thoughts we might have been thinking that created the exact movement of a specific facial muscle that we see on someone else's face. To the extent that we are right, we gain insight into the person we are looking at. We can also be wrong since we express ourselves somewhat differently.
The target of mirror neurons extends outside the body. When we see a car driving down the road, we not only infer the state of the car but that of the driver inside, even if we can't see the driver. And we do this for many cars all at the same time. The amount we can infer about the state of the other drivers' minds is limited, but it is sufficient to allow us to safely drive in crowded cities and freeways.
Our babies are born into the secret world. They are born with the skills to participate in it immediately. They don't recognize a boundary between self and other. There is only the secret world and all the wonders in it. Parents who bond with their babies are being re-initiated into the secret world. As the baby becomes initiated into the constructed world, learning words and concepts and proper behavior, the child is often forced to choose which world to attend to. The secret world never goes away, but most of us, parent and child alike, lose touch with it as the child grows up.
It seems to me that a pack of canines shares a similar secret world communicated (mostly) non-verbally. I don't know the exact nature of that secret world, but I suspect is similar to our own. (For example, a dog can do the same 3D positioning trick I described above.) I believe the reason dogs have been such successful human companions is that we can share some part of our secret worlds.
Whether we are walking down a crowded street or sitting at home with family, we are participating in a continual, omnidirectional communication with those around us, and the knowledge we infer from this is as real to us as any other sensory input.
The secret world is always there, but we are not often consciously aware of it. The experiences and circumstances of our lives often teach us to disconnect our consciousness from the secret world. There is a lot of emotional content shared in the secret world, and much of it is sad, and some of it is disturbing, so we learn to ignore it. There are people who can't hide from the secret world, and there are many who never experience it directly. But we all use the information from the secret world to allow us to live in (more-or-less) harmony with others.
Working apart
The previous post described the fundamental working relationship between the two hemispheres. That dance is what makes us human. But it's not the only relationship, nor even the best known.
The most public working relationship is that of the left brain speaking and acting for the whole brain. As previously pointed out, speech is mediated by Broca's area in the left brain, and most physical interaction with the world (touching, grasping, manipulating) is performed by the right hand, which is controlled by the left brain. This is why McGilchrist termed the left brain the Emissary.
The role of emissary means that the left brain is in a privileged role. If you accept that the left and right brains work independently and process information in completely different modes, then we have to consider that the left and right hemispheres may respond differently to the same stimuli, and there may be a conflict between the two responses. That raises the question of which response will be acted on with body and speech.
This is part of a larger question. I have greatly oversimplified the operation of the brain up to this point in order to create an understandable narrative. In fact, there are many parallel operations taking place in the brain at any one time, in both hemispheres. The brain is continually responding to stimuli, and it is also continually "choosing" which responses to act on. The process of "choosing" is not conscious but a complex equation involving both valence and arousal, which are in turn affected by context. Valence and arousal are independent dimensions of neural activity. Valence can be thought of as emotional content, and arousal can be thought of as emotional impact. The "choosing" is a learned response to evaluating valence, arousal, and context in real time.
The right hemisphere "chooses" one (or a few) response(s) among the many possibilities to present to the left brain. (I suspect one or a very small number because the corpus callosum that communicates the choice(s) is relatively small as brain pathways go.) Then the left brain "chooses" among its many possibilities, which include the right brain response(s), what will be acted on by body and speech. This puts the left brain in its privileged role.
This privileged role is what has led us to think of the left hemisphere as dominant. When the left hemisphere is severely damaged, we lose much of our ability to connect with the world, so we seem from the outside to not be the same person or not even "there". When the right hemisphere is severely damaged, we may talk and behave normally, and the loss of right-hemisphere function may not be so obvious to those who don't know us well.
It is a running theme on the TV series House that "people lie", and this doesn't mean the doctor believes people always do it intentionally. Furthermore, most psychological research must also deal with this issue. Reeves and Nass describe in The Media Equation how psychological experiments for the last 60 years have had to deal with the unreliability of verbal reports. The issue is that the left brain is "choosing" what to say. Generally, the most honest (and useful) response to most questions will come from the right brain since it is grounded in reality. But the left brain may choose to answer based on one of the many filters and processes it contains, ignoring the right brain response.
So the words and actions the left-brain initiates may represent only a faction among the brain's thought processes. Depending on ones life experiences, the distance between what is said and done may be miles from what is really going on in the brain. This distance can range from normal diplomatic speech to full repression of feelings resulting from serious abuse. These are learned responses to a complex world. Typically that learning is seen as necessary for survival (or advancement) of the whole by the left brain. But there are times when those lessons are not in our best interests.
Underlying the comments in this post is the assumption that the left and right hemispheres can carry multiple disagreeing thoughts and feelings. In a healthy person, the disagreement is typically minimal or well handled by the "choosing" mechanism. When the multiple thoughts and feelings diverge too much and are not handled well by our "choosing" mechanism, people feel considerable distress. Very often the underlying thoughts and feelings can't be changed. Then our only hope is to learn to "choose" better, and that isn't easy.
The left and right brains don't know the same things. The right brain has memory of its grounded reality. The left brain has memory of the its constructed reality. There is some evidence that the right brain has access to what the left brain knows, but not vice versa. This is consistent with the way that the right brain has access to the entire visual field while the left brain only has access to part of the right visual field, and the way that the right brain is aware of the entire body and the left brain is aware of only the right side. If true, this access makes the right brain a more complete picture of who we are than the left brain, and this is why McGilchrist termed the right brain the Master.
The asymmetry of the left-right divide in communication makes thinking and talking about the divide difficult. As I mentioned in my second post, the left brain can feel threatened by the exposure of its role and methods. I will repeat that I am not trying to denigrate the value or methods of the left brain: for every inappropriate coping mechanism is embodies there was undoubtedly an existential crisis making it necessary.
Do not take anything I say to mean the two brains are competing. They are both doing their best to protect and nurture our self as a whole, but they have very different views of the world and very different structures with which to deal with that world.
The most public working relationship is that of the left brain speaking and acting for the whole brain. As previously pointed out, speech is mediated by Broca's area in the left brain, and most physical interaction with the world (touching, grasping, manipulating) is performed by the right hand, which is controlled by the left brain. This is why McGilchrist termed the left brain the Emissary.
The role of emissary means that the left brain is in a privileged role. If you accept that the left and right brains work independently and process information in completely different modes, then we have to consider that the left and right hemispheres may respond differently to the same stimuli, and there may be a conflict between the two responses. That raises the question of which response will be acted on with body and speech.
This is part of a larger question. I have greatly oversimplified the operation of the brain up to this point in order to create an understandable narrative. In fact, there are many parallel operations taking place in the brain at any one time, in both hemispheres. The brain is continually responding to stimuli, and it is also continually "choosing" which responses to act on. The process of "choosing" is not conscious but a complex equation involving both valence and arousal, which are in turn affected by context. Valence and arousal are independent dimensions of neural activity. Valence can be thought of as emotional content, and arousal can be thought of as emotional impact. The "choosing" is a learned response to evaluating valence, arousal, and context in real time.
The right hemisphere "chooses" one (or a few) response(s) among the many possibilities to present to the left brain. (I suspect one or a very small number because the corpus callosum that communicates the choice(s) is relatively small as brain pathways go.) Then the left brain "chooses" among its many possibilities, which include the right brain response(s), what will be acted on by body and speech. This puts the left brain in its privileged role.
This privileged role is what has led us to think of the left hemisphere as dominant. When the left hemisphere is severely damaged, we lose much of our ability to connect with the world, so we seem from the outside to not be the same person or not even "there". When the right hemisphere is severely damaged, we may talk and behave normally, and the loss of right-hemisphere function may not be so obvious to those who don't know us well.
It is a running theme on the TV series House that "people lie", and this doesn't mean the doctor believes people always do it intentionally. Furthermore, most psychological research must also deal with this issue. Reeves and Nass describe in The Media Equation how psychological experiments for the last 60 years have had to deal with the unreliability of verbal reports. The issue is that the left brain is "choosing" what to say. Generally, the most honest (and useful) response to most questions will come from the right brain since it is grounded in reality. But the left brain may choose to answer based on one of the many filters and processes it contains, ignoring the right brain response.
So the words and actions the left-brain initiates may represent only a faction among the brain's thought processes. Depending on ones life experiences, the distance between what is said and done may be miles from what is really going on in the brain. This distance can range from normal diplomatic speech to full repression of feelings resulting from serious abuse. These are learned responses to a complex world. Typically that learning is seen as necessary for survival (or advancement) of the whole by the left brain. But there are times when those lessons are not in our best interests.
Underlying the comments in this post is the assumption that the left and right hemispheres can carry multiple disagreeing thoughts and feelings. In a healthy person, the disagreement is typically minimal or well handled by the "choosing" mechanism. When the multiple thoughts and feelings diverge too much and are not handled well by our "choosing" mechanism, people feel considerable distress. Very often the underlying thoughts and feelings can't be changed. Then our only hope is to learn to "choose" better, and that isn't easy.
The left and right brains don't know the same things. The right brain has memory of its grounded reality. The left brain has memory of the its constructed reality. There is some evidence that the right brain has access to what the left brain knows, but not vice versa. This is consistent with the way that the right brain has access to the entire visual field while the left brain only has access to part of the right visual field, and the way that the right brain is aware of the entire body and the left brain is aware of only the right side. If true, this access makes the right brain a more complete picture of who we are than the left brain, and this is why McGilchrist termed the right brain the Master.
The asymmetry of the left-right divide in communication makes thinking and talking about the divide difficult. As I mentioned in my second post, the left brain can feel threatened by the exposure of its role and methods. I will repeat that I am not trying to denigrate the value or methods of the left brain: for every inappropriate coping mechanism is embodies there was undoubtedly an existential crisis making it necessary.
Do not take anything I say to mean the two brains are competing. They are both doing their best to protect and nurture our self as a whole, but they have very different views of the world and very different structures with which to deal with that world.
Friday, March 11, 2011
Working together
In most people the left and right brains work together to create a recognizably human being. This wondrous dance is going on all the time, and the two hemispheres are always communicating with one another, but the communication isn't symmetrical.
The right brain is connected to the world, monitoring all the senses all the time we are awake. When the eyes are open, the right brain takes in a huge amount of information, including all the peripheral vision. Each eye has well over 100 million photoreceptors, the vast majority of them rods, which are very sensitive to light. The right brain pays attention to all of them and reacts when enough of them change in various patterns. The reaction often includes directing the eyes to turn toward the change and directing the left brain's attention to it.
The sense change might come from sound in the ears or a touch on the skin. Whether the change comes from those or vision, the right brain often directs the eyes to the perceived 3D location (which only the right brain knows) and tells the left brain to focus its attention and 2D vision on that sight.
Typically, the left brains drops whatever it was doing and places its attention on the center of vision (right center visual field only). It takes apart the visual field in a multistep process. First, the left visual cortex decomposes the 2D image into its component parts. Next, the decomposed visual field is passed through the various filters mentioned in the previous post to come up with an understanding or explanation or possibility of what created the change. Note that this change in attention is at the expense of whatever was being attended to previously.
Meanwhile, the right brain continues to pay attention to the changed area using the entire visual field. The right brain looks for threats to survival. Some threats may be built into our genes: there's some evidence that snakes and spiders may fall into this category and that relatively simple pattern recognition can invoke this response. Other threats are the result of learning from previous encounters. Such learning can be embodied in right-brain pattern recognition that responds quickly by directing the body to flee or otherwise react. A reaction that can be mediated only by the right brain reaction will happen very quickly, in most cases quickly enough to be successful.
Meanwhile the left brain will be decomposing the event both spatially and temporally. This takes time, so the threat better not be imminent if the left brain is involved. On the other hand, if it's a new threat, the right brain may not recognize it, so the slow, klunky analysis performed in parallel by the left brain may be the only thing that saves you. And if you survive the encounter, the analysis by the left brain can be returned to the right brain as a lesson that will allow faster response in the future.
The interaction of the left and right brains was just now described in terms of threats, but the same description can be made for opportunities. Suppose you are hungry. Walking through the jungle or savannah, your right brain takes everything in and finds all the normal sources of food very quickly. But what if there are no normal sources? A sufficiently starving right brain will notice anomalies in the environment that don't reach the threshold for food sources and direct the left brain to consider them. The left brain might deconstruct the anomaly and come up with a plan to turn it into food while the right brain continues to scan for known food and threats.
Thus the normal integrated operation of the two brains is for the right brain to direct the attention of the left brain to sensory anomalies while continuing to connect to the world, for the left brain to discover new aspects of the world based on those anomalies and return the new information to the right brain, and for the right brain to integrate the new information from the left brain into its larger world view for long term advantage. I call this the right-left-right paradigm. This process happens continually in healthy human beings, and this the process that has allowed our species to advance so radically for tens of thousands of years.
The right brain is connected to the world, monitoring all the senses all the time we are awake. When the eyes are open, the right brain takes in a huge amount of information, including all the peripheral vision. Each eye has well over 100 million photoreceptors, the vast majority of them rods, which are very sensitive to light. The right brain pays attention to all of them and reacts when enough of them change in various patterns. The reaction often includes directing the eyes to turn toward the change and directing the left brain's attention to it.
The sense change might come from sound in the ears or a touch on the skin. Whether the change comes from those or vision, the right brain often directs the eyes to the perceived 3D location (which only the right brain knows) and tells the left brain to focus its attention and 2D vision on that sight.
Typically, the left brains drops whatever it was doing and places its attention on the center of vision (right center visual field only). It takes apart the visual field in a multistep process. First, the left visual cortex decomposes the 2D image into its component parts. Next, the decomposed visual field is passed through the various filters mentioned in the previous post to come up with an understanding or explanation or possibility of what created the change. Note that this change in attention is at the expense of whatever was being attended to previously.
Meanwhile, the right brain continues to pay attention to the changed area using the entire visual field. The right brain looks for threats to survival. Some threats may be built into our genes: there's some evidence that snakes and spiders may fall into this category and that relatively simple pattern recognition can invoke this response. Other threats are the result of learning from previous encounters. Such learning can be embodied in right-brain pattern recognition that responds quickly by directing the body to flee or otherwise react. A reaction that can be mediated only by the right brain reaction will happen very quickly, in most cases quickly enough to be successful.
Meanwhile the left brain will be decomposing the event both spatially and temporally. This takes time, so the threat better not be imminent if the left brain is involved. On the other hand, if it's a new threat, the right brain may not recognize it, so the slow, klunky analysis performed in parallel by the left brain may be the only thing that saves you. And if you survive the encounter, the analysis by the left brain can be returned to the right brain as a lesson that will allow faster response in the future.
The interaction of the left and right brains was just now described in terms of threats, but the same description can be made for opportunities. Suppose you are hungry. Walking through the jungle or savannah, your right brain takes everything in and finds all the normal sources of food very quickly. But what if there are no normal sources? A sufficiently starving right brain will notice anomalies in the environment that don't reach the threshold for food sources and direct the left brain to consider them. The left brain might deconstruct the anomaly and come up with a plan to turn it into food while the right brain continues to scan for known food and threats.
Thus the normal integrated operation of the two brains is for the right brain to direct the attention of the left brain to sensory anomalies while continuing to connect to the world, for the left brain to discover new aspects of the world based on those anomalies and return the new information to the right brain, and for the right brain to integrate the new information from the left brain into its larger world view for long term advantage. I call this the right-left-right paradigm. This process happens continually in healthy human beings, and this the process that has allowed our species to advance so radically for tens of thousands of years.
The left brain
In the last post I described most of the primary features of the right brain. It may have seemed that I covered most of what it means to be human. Now I will add the rest.
The left brain is much different than the right brain. The difference is not a matter of degree but of purpose. The separation of function in the hemispheres of our brains is critical to both our survival as individuals and our success as a species.
The left brain doesn't see the world. It sees this and that and the other thing: fragments in space and time. Beyond that, it sees the world through a multi-level haze of filters. These filters come from previous experiences. We experience these filters as moods, opinions, theories, convictions, prejudices, etc. At any one point in time the left brain may be interpreting the world through any number of filters.
In the left-brain mode of perception we see what McGilchrist calls re-presentations. These are constructions of the left brain based on the filters in effect at that time. For instance, if you ask someone about her relatives, you will usually get answers based on the stories that she tells herself about them, answers that may not agree with direct perception. This is a very difficult concept that will be expanded in a later post.
The left brain doesn't perceive the flow of time. The left brain understands time intervals and events and can string those intervals and events together to create the illusion of the flow, but only as long as that string is maintained.
The left brain focuses attention. It can choose a sense to follow. With effort it can pay attention to two senses and connect their occurrences.
Specifically, the left brain can focus its attention on the central portion of the right visual field. This is a relatively small area that roughly corresponds to densest aggregation of cones in the center of the eye, and only the right side of that. The cones provide our highest resolution sight, so the brain focusing on something with this vision makes a powerful tool.
The left brains sees this area in 2D. It doesn't sense or appreciate depth. Note that this small area on the curved visual field approximates a flat surface very effectively, so there is no real loss of perception.
The primary feature of the left brain's 2D perception is the discovery and tracking of boundaries. The left brain is continually finding boundaries of what is in its visual field. In fact, it does this to the extent that the boundaries often become more noticeable and important than the entities they bound.
The primary activity of the left brain is to deconstruct and reconstruct the world. Its view of the world starts with the accumulation of sensory fragments, and it proceeds to play with these building blocks to try and make sense of the world. The result of this play is the moods, opinions, theories, convictions, prejudices, etc., mentioned above that become filters to further perception.
In effect, the primary activity of the left brain involves a feedback loop between viewing the world through filters and continually updating or reinforcing those filters. More on this later.
The secondary activity of the left brain is to be the primary agent of action. Much human action is verbal, and generally only the left brain has access to the voice. The complex manipulations of breathing and the vocal chords required for speech are so complicated (taking up brain space) that it makes sense to centralize them in one place, and that place is Broca's area in the left hemisphere. The next most common human action is touch, which involves touching something, grasp, and manipulation. These actions are also concentrated in the left hemisphere, which is why we think of most people as right handed.
Memory in the left brain is problematical. The left brain can only remember what got in past the filters, and what is remembered is a collection of fragments strung together with whatever form of organization was in effect at the time the memories were created. The recall of memories from the left brain is often found to be faulty. The filters obscure and misrepresent reality. The filters in place during recall are often different from the filters in place when the memories were created, leading to misinterpretation. And the organization of the fragments is subject to revision when the memory is recalled.
These are the primary functions of the left brain. I hope you will note that healthy human beings are not characterized by either this or the right brain description. Being human is a dance between the hemispheres that magically gives us the best of both ways of approaching the world. In the next post I will start describing the interaction.
The left brain is much different than the right brain. The difference is not a matter of degree but of purpose. The separation of function in the hemispheres of our brains is critical to both our survival as individuals and our success as a species.
The left brain doesn't see the world. It sees this and that and the other thing: fragments in space and time. Beyond that, it sees the world through a multi-level haze of filters. These filters come from previous experiences. We experience these filters as moods, opinions, theories, convictions, prejudices, etc. At any one point in time the left brain may be interpreting the world through any number of filters.
In the left-brain mode of perception we see what McGilchrist calls re-presentations. These are constructions of the left brain based on the filters in effect at that time. For instance, if you ask someone about her relatives, you will usually get answers based on the stories that she tells herself about them, answers that may not agree with direct perception. This is a very difficult concept that will be expanded in a later post.
The left brain doesn't perceive the flow of time. The left brain understands time intervals and events and can string those intervals and events together to create the illusion of the flow, but only as long as that string is maintained.
The left brain focuses attention. It can choose a sense to follow. With effort it can pay attention to two senses and connect their occurrences.
Specifically, the left brain can focus its attention on the central portion of the right visual field. This is a relatively small area that roughly corresponds to densest aggregation of cones in the center of the eye, and only the right side of that. The cones provide our highest resolution sight, so the brain focusing on something with this vision makes a powerful tool.
The left brains sees this area in 2D. It doesn't sense or appreciate depth. Note that this small area on the curved visual field approximates a flat surface very effectively, so there is no real loss of perception.
The primary feature of the left brain's 2D perception is the discovery and tracking of boundaries. The left brain is continually finding boundaries of what is in its visual field. In fact, it does this to the extent that the boundaries often become more noticeable and important than the entities they bound.
The primary activity of the left brain is to deconstruct and reconstruct the world. Its view of the world starts with the accumulation of sensory fragments, and it proceeds to play with these building blocks to try and make sense of the world. The result of this play is the moods, opinions, theories, convictions, prejudices, etc., mentioned above that become filters to further perception.
In effect, the primary activity of the left brain involves a feedback loop between viewing the world through filters and continually updating or reinforcing those filters. More on this later.
The secondary activity of the left brain is to be the primary agent of action. Much human action is verbal, and generally only the left brain has access to the voice. The complex manipulations of breathing and the vocal chords required for speech are so complicated (taking up brain space) that it makes sense to centralize them in one place, and that place is Broca's area in the left hemisphere. The next most common human action is touch, which involves touching something, grasp, and manipulation. These actions are also concentrated in the left hemisphere, which is why we think of most people as right handed.
Memory in the left brain is problematical. The left brain can only remember what got in past the filters, and what is remembered is a collection of fragments strung together with whatever form of organization was in effect at the time the memories were created. The recall of memories from the left brain is often found to be faulty. The filters obscure and misrepresent reality. The filters in place during recall are often different from the filters in place when the memories were created, leading to misinterpretation. And the organization of the fragments is subject to revision when the memory is recalled.
These are the primary functions of the left brain. I hope you will note that healthy human beings are not characterized by either this or the right brain description. Being human is a dance between the hemispheres that magically gives us the best of both ways of approaching the world. In the next post I will start describing the interaction.
The right brain
In the last post I presented what is well known (and not particularly controversial) about the functions of the two brains. In this post I will tell you what I think is happening. Much of it is controversial. Most of it has some evidence, though I will not present the evidence. If it resonates with you and you want to learn more, I encourage you to read the source materials for the blog, given in the first post.
First I will describe the right brain. This is not arbitrary. While neuroscience has previously referred to the left brain as the primary or dominant hemisphere, those labels are being called into question. For example, in the book titled The Master and His Emissary, the master is the right brain, and the emissary is the left brain. I hope you will agree after I describe this relation that this may be true.
The right brain sees the world as it is. It perceives the world in concrete terms. It doesn't interpret the world through any sort of symbolism or abstraction or rubrik. It perceives the world in real time. It doesn't form opinions about the world; it doesn't judge what it perceives.
The right brain sees the world as a flow in time. One microsecond flows into the next, with no boundary or step.
The right brain perceives the world through all the senses all the time and integrates the senses into a single flow. It doesn't focus on any one sense or any one sensation.
In the last post I said that the left brain only has access to the right visual field. Further, it only has access to the center of the right side of the visual field. I'll say more about that later. I bring that up to contrast it to the visual access of the right brain. The right brain has access to both the left and right sides of the visual field, and it has access to peripheral vision, which the left brain does not. Thus, if the left brain is damaged, the right brain still has access to the full visual field, quite different from when the right brain is damaged.
The condition called asomatognosia illustrates the difference in perception. A person with a right brain stroke, able to perceive only with the left brain, may be unable to perceive the left side of the body, depending on the extent of right brain injury. If so, the person will often deny that the left side of the body even exists. Such a person may complain that someone else is in bed with them, because that arm isn't theirs. By contrast, a person with left brain stroke will generally not experience asomatognosia. Such a person will have full body awareness, though sensation from and control of the right side of the body may be compromised. The difference is that the right brain was aware of that side of the body all along and so has a memory of it.
The right brain sees the world in 3D. This is aided by the availability of peripheral vision. It knows how objects fit into 3-space and understands how they relate to one another. It knows about depth and occlusion. Note that this 3D view doesn't depend on binocular vision, which only works in a narrow range of near distances, so one-eyed people still see the world in 3D. This 3D perception of the world comes from moving through the world and seeing how things change their relation as we move.
The right brain holds our true memories of the past. These are sensual memories of the events that actually happened, integrating all the senses with the emotional context that accompanied them. A recent 60 Minutes episode reported on "superior autobiographical memory", in which 6 people worldwide have been identified as able to recall every event in their lives. It is likely that we all have some version of this kind of memory. The issue is recall.
The right brain can extrapolate reality into the future. This doesn't involve theorizing, it is just a continuous extension of current knowledge a few milliseconds into the future. This is how a professional baseball player can hit a pitch when it is known that his eye-to-arm reaction time is much of the time it takes a baseball to travel from the pitcher's mound to the plate. He doesn't "think" about hitting the ball so much as "seeing" it a bit early. (And it's obviously not perfect.) The professional baseball player also extrapolates the detailed body motions of the pitcher into an understanding of where and how fast the ball will arrive. Personally, I've experienced catching something I knocked off a table, without any time to think about it. These are all abilities of the right brain.
The right brain doesn't perceive boundaries. In its 3D world view it doesn't see the boundaries between the objects we normally think of. Moreover, it doesn't see a boundary between itself and the rest of the world. It doesn't see itself as an active agent in the world. It sees itself as continuously connected to all it perceives, including other people.
In the next post I will describe the left brain. It is much different from the right brain, and I have hinted at some of the differences already.
First I will describe the right brain. This is not arbitrary. While neuroscience has previously referred to the left brain as the primary or dominant hemisphere, those labels are being called into question. For example, in the book titled The Master and His Emissary, the master is the right brain, and the emissary is the left brain. I hope you will agree after I describe this relation that this may be true.
The right brain sees the world as it is. It perceives the world in concrete terms. It doesn't interpret the world through any sort of symbolism or abstraction or rubrik. It perceives the world in real time. It doesn't form opinions about the world; it doesn't judge what it perceives.
The right brain sees the world as a flow in time. One microsecond flows into the next, with no boundary or step.
The right brain perceives the world through all the senses all the time and integrates the senses into a single flow. It doesn't focus on any one sense or any one sensation.
In the last post I said that the left brain only has access to the right visual field. Further, it only has access to the center of the right side of the visual field. I'll say more about that later. I bring that up to contrast it to the visual access of the right brain. The right brain has access to both the left and right sides of the visual field, and it has access to peripheral vision, which the left brain does not. Thus, if the left brain is damaged, the right brain still has access to the full visual field, quite different from when the right brain is damaged.
The condition called asomatognosia illustrates the difference in perception. A person with a right brain stroke, able to perceive only with the left brain, may be unable to perceive the left side of the body, depending on the extent of right brain injury. If so, the person will often deny that the left side of the body even exists. Such a person may complain that someone else is in bed with them, because that arm isn't theirs. By contrast, a person with left brain stroke will generally not experience asomatognosia. Such a person will have full body awareness, though sensation from and control of the right side of the body may be compromised. The difference is that the right brain was aware of that side of the body all along and so has a memory of it.
The right brain sees the world in 3D. This is aided by the availability of peripheral vision. It knows how objects fit into 3-space and understands how they relate to one another. It knows about depth and occlusion. Note that this 3D view doesn't depend on binocular vision, which only works in a narrow range of near distances, so one-eyed people still see the world in 3D. This 3D perception of the world comes from moving through the world and seeing how things change their relation as we move.
The right brain holds our true memories of the past. These are sensual memories of the events that actually happened, integrating all the senses with the emotional context that accompanied them. A recent 60 Minutes episode reported on "superior autobiographical memory", in which 6 people worldwide have been identified as able to recall every event in their lives. It is likely that we all have some version of this kind of memory. The issue is recall.
The right brain can extrapolate reality into the future. This doesn't involve theorizing, it is just a continuous extension of current knowledge a few milliseconds into the future. This is how a professional baseball player can hit a pitch when it is known that his eye-to-arm reaction time is much of the time it takes a baseball to travel from the pitcher's mound to the plate. He doesn't "think" about hitting the ball so much as "seeing" it a bit early. (And it's obviously not perfect.) The professional baseball player also extrapolates the detailed body motions of the pitcher into an understanding of where and how fast the ball will arrive. Personally, I've experienced catching something I knocked off a table, without any time to think about it. These are all abilities of the right brain.
The right brain doesn't perceive boundaries. In its 3D world view it doesn't see the boundaries between the objects we normally think of. Moreover, it doesn't see a boundary between itself and the rest of the world. It doesn't see itself as an active agent in the world. It sees itself as continuously connected to all it perceives, including other people.
In the next post I will describe the left brain. It is much different from the right brain, and I have hinted at some of the differences already.
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