This blog is, in part, an effort to connect dots --- particularly among the books that have come off my Bookshelf. A number of dots connected in my mind as I read Leonard Mlodinow's Euclid's Window.
Euclid's Window opens in Greek antiquity in the port of Miletus on the west coast of what is now Turkey. Mlodinow asserts that a "revolution in human thought, a mutiny against superstition and sloppy thinking," occurred here in the 7th century BCE. Around 620 B.C., Thales of Miletus, who Mlodinow describes as humanity's "first scientist or mathematician," lived here and is purportedly responsible for the systematization of geometry, a methodology that would later be incorporated in Euclid's Elements. This blog first mentioned the scientific contributions of the Milesians in a prior post (see March 28, 2010 post), noting historian David Lindberg's comment, "[I]n the answers offered by these Milesians we find no personification or deification of nature; a conceptual chasm [that] separates their worldview from the mythological world of Homer and Hesiod. The Milesians left the gods out of the story. What they may have thought about the Olympian gods we do not (in most cases) know; but they did not invoke the gods to explain the origin, nature or cause of things." (See March 24, 2010 post). The inference from Lindberg's observation is that when the human mind frees itself from myth, religion, and superstition --- the types of "beliefs" that Michael Shermer wrote about in The Believing Brain (see June 12, 2011 post) --- scientific progress is unshackled.
While Mlodinow does not make the same observation about the Milesians, he does seem to fall into a trap that Lindberg encourages historians to avoid: blaming Christianity entirely for Europe's failure to maintain the scientific progress that the Greek's initiated before the first millennium A.D. (see March 24, 2010 post). Apparently relying on Edward Gibbon, Mlodinow cites the Christians for burning down the greatest library of its era at Alexandria, Egypt and all the scientific and philosophical works that were part of that library. This claim may not be true or entirely true, but the fact the Mlodinow seems to harbor this belief, as revealed in this reference and other statements he makes, strains his credibility as a writer of science history (at least about science and mathematics in the era of the Dark and Middle Ages). It is true that once the institutions of the Dark and Middle Ages lost touch with Greek scientific inquiry and knowledge, institutional biases developed that made it very difficult for that knowledge to be rediscovered, and among those institutions was the Catholic Church. Yet, as Lindberg documents, those institutions also had a small role in the rediscovery of Greek science and thought.
As Mlodinow moves from his portraits of the geometers and Euclid to Descartes to Carl Gauss (and Reimann), the reader senses the impending merger of geometry and physics (or perhaps the impending takeover of geometry by physics) with the development of non-Euclidean geometry. Since the times following Euclid, Euclid's Fifth Postulate (the parallel postulate) had proven troublesome. Euclid stated a proposition that would determine whether two co-planar lines were parallel, converging, or diverging: take two lines and cross them with a third line; if the sum of the two inner angles on the same side of the crossing line is less than two right angles (180 degrees), then the two lines are converging (on that side of the crossing line). The postulate seems intuitively correct. The problem is that the fifth postulate could not be proven as a theorem would be proven. It was assumed as a fact, until non-Euclidean geometry began to address surfaces that are curved and the parallel postulate failed. Geometry began not only to take a hard look at spherical surfaces and topography --- the earth, but it began to turn its attention to space.
Enter Albert Einstein, relativity, and the influence of gravity on the shape of space. Even Mlodinow's brief discussions of Euclid, Descartes, and Gauss made me recall Rita Carter's discussion of the posthumous study of Einstein's brain in Mapping the Mind (see November 6, 2011 post). Carter reports that researchers at McMaster University in Canada found that Einstein's brain "was different from most in several ways, the most notable being that two sulci (infolds) in the parietal cortex had merged during development, creating a single enlarged patch of tissue where usually there would be a division. In normal people, one of these areas is primarily involved in spatial awareness, while the other does (among other things) mathematical calculation. The merging of these two areas in Einstein's brain," Carter speculates, "may well account for his unique ability to translate his 'vision' of space-time into the most famous mathematical equation of all time, e=mc2." Here Carter has been discussing synaethesia, the phenomenon where, because of the close proximity of two parts of the brain, there is a merging of sensory phenomena: e.g., hearing the sound of a certain word or number takes is associated with a certain color. Have the brains of certain mathematicians who can develop mathematical theories or even practical algorithms that describe physical phenomena or physical space developed in a way that facilitates their mathematical skill and insights, in contrast to the brains of most humans? Mlodinow's historical survey of the history of geometry certainly makes one wonder about that.
Reading Euclid's Window also reminded me of a quote from Michael Shermer that I mentioned in the June 12, 2011 post, "We are not equipped to perceive atoms and germs, on the one end of the scale, or galaxies and expanding universes, on the other end." Yet clearly, as Mlodinow's portrait of Einstein and later Edward Witten moves from relativity and quantum mechanics to the "standard model" and ultimately to string theory, it is clear that some minds are clearly capable of not only envisioning atoms, but even smaller particles, and some minds (sometimes the same minds) are capable of envisioning galaxies and expanding universes. Without this capability, Mlodinow would never have had a story to tell. Mlodinow sums this up as follows: "Through Euclid's window we have discovered many gifts, but he could not have imagined where they would take us. To know the stars, to imagine the atom, and to begin to understand how these pieces of the puzzle fit into the cosmic plan is for our species a special pleasure, perhaps the highest. Today, our knowledge of the universe embraces distances so vast we will never travel them and distances so tiny we will never see them. We contemplate times no clock can measure, dimensions no instrument can detect, and forces no person can feel. We have found that in variety and even in apparent chaos, there is simplicity and order."
This is not a deep book. It is written for the general public who has an interest in mathematics and the history of science. I began by criticizing Mlodinow for his knowledge of history in the Dark and Middle Ages, but by the end of the book and the discussion of string theory, I came to conclude that I wished I had read this book before embarking on other deeper books about string theory.
Sunday, November 20, 2011
Wednesday, November 16, 2011
David Liss, A Conspiracy of Paper (2000)
The year is 1719. The scene is London, England. King George I, recently arrived from Germany, sits on the throne of England. Unlike the French, the English have not yet created a local or national police force to protect its citizens. The entrepreneurial class filled the official void, and established themselves as "thief-takers," bounty hunters hired to capture criminals. The most notorious of the thief-takers, Jonathan Wild, exploited his status to form an organized crime gang of thieves who stole property only to be hired by the victim, who would pay for its return, to "find" the same stolen property.
England is suffering financially at this time under the weight of a growing national debt because of the War of Spanish Succession. The South Sea Company, a business organized in the early 18th century as a stock company, buys half of the national debt in exchange for its stock, pursuant to a plan to convert that debt to lower interest debt that would ease the government's financial burden, but also provide the South Sea Company with steady revenue. The South Sea Company then pursued a program to drive up the price of its stock and a speculative frenzy ensued. By 1720, the infamous South Sea Bubble, the first stock market crash, occurred, leading to bankruptcies and other financial problems across Europe.
There is a nascent, unregulated stock market operating out of coffeehouses on and around Exchange Alley, where "stock jobbers" trade in company stocks. Stock jobbers are not held in high reputation, apparently for all the reasons that, over 200 years later, the United States of America established a Security and Exchange Commission to regulate this trade.
All of this is true, and against this background, David Liss' fictional story of a competing thief-taker, Benjamin Weaver, begins in earnest. Weaver, a Jew among the predominantly Protestant community of England, has assimilated reasonably well. He has recently become a "thief-taker," retired from his earlier professional roles as highwayman and competitive boxer. He now competes with Jonathan Wild for clients, but unlike Wild he forswears the unethical practice of stealing only to later "find" the stolen booty for a fee. Weaver is the grandson of Miguel Lienzo, the protagonist of Liss' third novel, The Coffee Trader, a prequel of sorts to A Conspiracy of Paper. Liss' oeuvre, if we want to call it that is not generic historical fiction, but economic historical fiction. The marketplace is as much a part of his work as the cast of characters and the plot.
A murder has allegedly occurred, and A Conspiracy of Paper is essentially a whodonit. The precise "who" is known early on, but the "official" conclusion is that the death was merely an accident. Others, however, suspect foul play --- a "conspiracy." Suspects abound as to who is really behind the conspiracy.
This is the period of the English Enlightenment. John Locke is fifteen years in the grave. David Hume (see February 27, 2011, post) is only 8 years old. But Isaac Newton is in the golden era of his illustrious life. Bernard Mandeville was editing his Fable of the Bees (see January 30, 2010 post), and George Berkeley was active trying to undo Locke's view of a materialist world.
To solve the murder mystery, however, none of these Enlightenment philosophers contributes to a method of investigation. A French mathematician and Catholic philosopher, Blaise Pascal, provides a source of inspiration. Probability theory is invoked. And so is right brain/left brain wisdom. I refer to the mind's right brain capacity to make intuitive hunches, and the left brain capacity to meditate, analyze, and sort through information. Weaver's friend, Elias, advises him, "[Pascal's] thinking is precisely what will allow you to resolve this matter, for you must work with probability rather than facts. If you can only go by what is probable, you will sooner or later learn the truth." Weaver responds, "Are you suggesting I conduct this matter by randomly choosing paths of inquiry?" Elias responds, "Not randomly. If you know nothing with certainty, but you guess reasonably, acting upon those guesses offers the maximum chance of learning who did this with the minimal amount of failure. Not acting offers no chance of discovery. The great mathematical minds of the last century, Boyle, Wilkins, Glanvil, Gassendi --- have set forth the rules by which you are to think if you are to find your murderer. You will not act on what your eyes and ears show you, but on what your mind thinks probable."
The murder victim is Weaver's father --- the son of Miguel Lienzo, who migrated from Amsterdam to London with his brother. Weaver's father is a stock-jobber, and Weaver suspects, as information starts to become available, that his father uncovered a conspiracy to manipulate the value of South Sea Company stock.
Only later in the novel, as Weaver laments how difficult it has become to bring the investigation of his father's murder to a conclusion, and he says, "Your philosophy [referring to Elias] has brought me this far, but I cannot see how it takes me much farther," Elias responds, "If philosophy no longer yields results, perhaps it is not because you have reached your limit to understanding philosophy. I think it is far more probable that philosophy had done what philosophy can do, and you would be wise to trust your instincts as fighter and a thief-taker. . . Trust your instincts." What would Sherlock Holmes say?
In the end the crime is solved, not because of instinct, but because a crucial piece of information suddenly falls into Weaver's lap -- the revelation of a lie that reveals the identity of the murderer. The revelation is not accidental. Jonathan Wild pushed the information in front of Weaver to help him out. The conspiracy behind the murder of his father turns out to be a vastly different conspiracy than Weaver initially postulated and conceived. Probabilities and beliefs did not solve this murder. Factual information did, much in the way that scientific experimentation during the Enlightenment era was undermining long-held beliefs that were products of mental reasoning, faith, and bias.
Decisions are made based on probabilities because we have incomplete information, uncertainty. Hume essentially made the point (see February 27, 2011 post), and he could not have been the first. Some people have access to more information than others and can act on superior information to their advantage. Wild is such a person, and in Wild's version of thief-taking where the taker is also the thief, it is just an early version of what we now call insider-trading. A Conspiracy of Paper was written and published as the 20th century came to a close and the technology stock bubble burst. And stock market manipulation and insider trading have not disappeared either. Liss is an excellent storyteller, and he is very clever at detecting in the annals of economic history, just as he did too in The Coffee Trader, the parallel times of the human past that reverberate in the modern mind.
England is suffering financially at this time under the weight of a growing national debt because of the War of Spanish Succession. The South Sea Company, a business organized in the early 18th century as a stock company, buys half of the national debt in exchange for its stock, pursuant to a plan to convert that debt to lower interest debt that would ease the government's financial burden, but also provide the South Sea Company with steady revenue. The South Sea Company then pursued a program to drive up the price of its stock and a speculative frenzy ensued. By 1720, the infamous South Sea Bubble, the first stock market crash, occurred, leading to bankruptcies and other financial problems across Europe.
There is a nascent, unregulated stock market operating out of coffeehouses on and around Exchange Alley, where "stock jobbers" trade in company stocks. Stock jobbers are not held in high reputation, apparently for all the reasons that, over 200 years later, the United States of America established a Security and Exchange Commission to regulate this trade.
All of this is true, and against this background, David Liss' fictional story of a competing thief-taker, Benjamin Weaver, begins in earnest. Weaver, a Jew among the predominantly Protestant community of England, has assimilated reasonably well. He has recently become a "thief-taker," retired from his earlier professional roles as highwayman and competitive boxer. He now competes with Jonathan Wild for clients, but unlike Wild he forswears the unethical practice of stealing only to later "find" the stolen booty for a fee. Weaver is the grandson of Miguel Lienzo, the protagonist of Liss' third novel, The Coffee Trader, a prequel of sorts to A Conspiracy of Paper. Liss' oeuvre, if we want to call it that is not generic historical fiction, but economic historical fiction. The marketplace is as much a part of his work as the cast of characters and the plot.
A murder has allegedly occurred, and A Conspiracy of Paper is essentially a whodonit. The precise "who" is known early on, but the "official" conclusion is that the death was merely an accident. Others, however, suspect foul play --- a "conspiracy." Suspects abound as to who is really behind the conspiracy.
This is the period of the English Enlightenment. John Locke is fifteen years in the grave. David Hume (see February 27, 2011, post) is only 8 years old. But Isaac Newton is in the golden era of his illustrious life. Bernard Mandeville was editing his Fable of the Bees (see January 30, 2010 post), and George Berkeley was active trying to undo Locke's view of a materialist world.
To solve the murder mystery, however, none of these Enlightenment philosophers contributes to a method of investigation. A French mathematician and Catholic philosopher, Blaise Pascal, provides a source of inspiration. Probability theory is invoked. And so is right brain/left brain wisdom. I refer to the mind's right brain capacity to make intuitive hunches, and the left brain capacity to meditate, analyze, and sort through information. Weaver's friend, Elias, advises him, "[Pascal's] thinking is precisely what will allow you to resolve this matter, for you must work with probability rather than facts. If you can only go by what is probable, you will sooner or later learn the truth." Weaver responds, "Are you suggesting I conduct this matter by randomly choosing paths of inquiry?" Elias responds, "Not randomly. If you know nothing with certainty, but you guess reasonably, acting upon those guesses offers the maximum chance of learning who did this with the minimal amount of failure. Not acting offers no chance of discovery. The great mathematical minds of the last century, Boyle, Wilkins, Glanvil, Gassendi --- have set forth the rules by which you are to think if you are to find your murderer. You will not act on what your eyes and ears show you, but on what your mind thinks probable."
The murder victim is Weaver's father --- the son of Miguel Lienzo, who migrated from Amsterdam to London with his brother. Weaver's father is a stock-jobber, and Weaver suspects, as information starts to become available, that his father uncovered a conspiracy to manipulate the value of South Sea Company stock.
Only later in the novel, as Weaver laments how difficult it has become to bring the investigation of his father's murder to a conclusion, and he says, "Your philosophy [referring to Elias] has brought me this far, but I cannot see how it takes me much farther," Elias responds, "If philosophy no longer yields results, perhaps it is not because you have reached your limit to understanding philosophy. I think it is far more probable that philosophy had done what philosophy can do, and you would be wise to trust your instincts as fighter and a thief-taker. . . Trust your instincts." What would Sherlock Holmes say?
In the end the crime is solved, not because of instinct, but because a crucial piece of information suddenly falls into Weaver's lap -- the revelation of a lie that reveals the identity of the murderer. The revelation is not accidental. Jonathan Wild pushed the information in front of Weaver to help him out. The conspiracy behind the murder of his father turns out to be a vastly different conspiracy than Weaver initially postulated and conceived. Probabilities and beliefs did not solve this murder. Factual information did, much in the way that scientific experimentation during the Enlightenment era was undermining long-held beliefs that were products of mental reasoning, faith, and bias.
Decisions are made based on probabilities because we have incomplete information, uncertainty. Hume essentially made the point (see February 27, 2011 post), and he could not have been the first. Some people have access to more information than others and can act on superior information to their advantage. Wild is such a person, and in Wild's version of thief-taking where the taker is also the thief, it is just an early version of what we now call insider-trading. A Conspiracy of Paper was written and published as the 20th century came to a close and the technology stock bubble burst. And stock market manipulation and insider trading have not disappeared either. Liss is an excellent storyteller, and he is very clever at detecting in the annals of economic history, just as he did too in The Coffee Trader, the parallel times of the human past that reverberate in the modern mind.
Sunday, November 6, 2011
Rita Carter, Mapping the Mind (Rev. 2010)
Five postings in 2011 on books and subjects related to the mind and brain, and I was consciously aware of that fact and a desire to move on to something new. But as I wrapped up V.S. Ramachandran's The Tell-Tale Brain (see previous post), his remark that as neuroscientists map the brain they are "grouping their way toward the periodic table of elements" reminded me that a book on The Bookshelf that I had purchased last year, Rita Carter's Mapping the Mind, was waiting to be read. I found this book at the bookshop at the conclusion of the American Museum of Natural History's exhibit on The Brain. I recalled that what impressed me toward a purchase was the exquisite drawings of the brain, many of which included arrows to illustrate the interconnectedness of specific brain regions to explain a specific neuronal process. For those who are not practicing neurologists, a picture can nicely supplement a thousand words.
By the end of Mapping the Brain, I wondered if this should have been the first book I ever read on the brain. Would I have better appreciated all the other material I have read on this subject if I had already read this book? I can't answer that, but studying Rita Carter's text after I had read these other books, many of which are discussed or mentioned in prior posts, was facilitated by my prior exposure to the subject. Either way, Mapping the Brain is a good overview and introduction to the brain and a good review as well.
Ramachandran's analogy that neuroscience's understanding of the brain is moving in the direction of establishing something akin to chemistry's periodic of table of elements is best left as a metaphor rather than a suggestion of equivalence (as I think the statement was intended). It is fair to say, like the periodic of table of elements, that the brain is organized, but it is not sequential in the same sense that the elements can be organized sequentially according to their atomic weight or related in their properties as part of one of 18 different groups. While thinking about this, it crossed my mind that evolutionary age would be one way of sequentially organizing the parts of the brain. Antonio Damasio did something like this in Self Comes to Mind (see April 8, 2011 post), describing the sequential evolution of the brain stem, the limbic system, and ultimately the cerebral cortex. But the brain is indeed very complex, as Carter notes in her closing paragraph, when she says that "today's mind voyagers are discovering a biological system of awe-inspiring complexity." One could also try to organize the parts of the brain sequentially, starting with a particular sensory input, and follow the connections to other parts of the brain to conscious awareness and action (or unconscious action, as the case may be) that ensues. In the end, however, that effort would not be particularly useful given the multi-layer network of sensory inputs that are processed simultaneously, including the presence of variable emotional reactions in connection with a particular sensory input that could stimulate a different behavioral outcome.
Both Carter and Ramachandran caused me to question a statement I made in a prior post (June 12, 2011 post) while discussing Michael Shermer's The Believing Brain. I wrote:
"I strongly suspect that if we dissected human brains and a network of connected neurons from a representative sample of humans, we would find a very high level of near identity among brains. There will be some differences due to DNA, and there will be some pathological differences as well, perhaps caused during embryonic development. But I believe that by and large we will find that human brains, neuron by neuron, are organized and folded and layered in substantially identical ways." There is substantial truth in my remark --- I did not say identical, but I did say "near identity" and "substantially identical." These words came at the risk of maybe overstating the case. Carter writes, "Human brains are constructed along fairly standard lines and so we all tend to see the world in a fairly standard way." And as I noted, there are differences due to DNA, pathological injury, and embryonic development. But I overlooked perhaps the largest exception --- experience (nurture) and its impact on memory -- and what is referred to as synaptic plasticity. And it is long-term memory -- enhanced by repeated experiences in some that others do not share --- that gives rise to our autobiographical self and what makes each one of us unique. So while we may "tend to see the world in a fairly standard way," Carter notes:
"Every brain constructs the world in a slightly different way from any other because every brain is different. The sight of an external object will vary from person to person because no two people have precisely the same number of motion cells, magenta-sensitive cells, or straight line cells. . . . An individual's view is formed both by their genes and by how their brain has been moulded by experience. Musicians, for instance, have brains which are physically different from others and which work differently when they play or hear music. . . . Extraordinary individual ways of seeing things may also arise from strange 'quirks' of brain development. Albert Einstein, for instance, had a very oddly constructed brain which might account for his astonishing insights into the nature of space and time."
Carter's treatment of language pretty much follows that of Ramachandran. And her treatment of memory restates much of what Antonio Damasio (see April 8, 2011 post) and Daniel Schacter (see September 20, 2011 post) discuss, but I still learned something new. For example, "Episodes that are destined for long-term memory are not lodged there right away. The process of laying them down permanently takes up to two years. Until then they are still fragile and may quite easily be wiped out. It is this replay from hippocampus to cortex and back again -- a process known as consolidation, that slowly turns fleeting impressions into long-term memories. . . Much of the hippocampal replay is thought to happen during sleep. Recordings from hippocampal cells show them engaging in a 'dialogue' with cortical cells, during which they signal one another, back and forth, in a call-and-reply formation. Some of this is known to take place during the 'quiet' phase of sleep, when dreaming, if it occurs at all, and is vague and instantly forgotten. Until memories are fully encoded in the cortex they are still fragile and may quite easily be wiped out. And even when they are established, they are not fixed. A memory is not, in fact, a recollection of an experience but the recollection of the last time you recalled the experience. Hence our memories are constantly changing and redeveloping. The process by which a memory changes is more or less the same as the consolidation process that lays it down for the first time. As we will see, each time we recall something, it is changed a little because it becomes mixed up with things that are happening in the present. Reconsolidation is a process by which this slightly altered memory effectively replaces the previous one, writing over it, so to speak, rather like re-recording over a rewritable DVD." I mentioned this phenomenon in the September 20, 2011 post discussing Daniel Schacter's discussion of the consistency bias, whereby the brain infers past beliefs from our current state and the reference to Joseph LeDoux's discussion of reconsolidation. Carter explains it better.
I also learned that not all memories are stored in cortical areas. While long-term memories are initially stored in the hippocampus, as described above, over the course of roughly two years they are transferred to the cortex and the hippocampus is no longer required for their retrieval. These memories are distributed in the same parts of the brain that encoded the original experience. So sounds are found in the auditory cortex, taste and skin sensory memories are found in the somatosensory cortex, and sight in the visual cortex. But procedural -- "how to" --- memories are stored outside of the cortex, in the cerebellum and putamen, and fear memories are stored in the amygdala.
Carter also addresses, albeit briefly, the subject of imagination, which I have touched on in several previous postings (see, for instance, July 30, 2011 post and May 22, 2011 post) and describes the connection to memory. "Our ability to conjure up scenarios which have not actually happened is prodigious. Imaginative capacity runs along a spectrum from the mundane skills required to envisage what your supper might taste like if you combined the onion, mushrooms, and left over chicken in the fridge with some curry sauce, through to the awe-inspiring visions of artists, writers, and excitable children. Even the humblest of these skills outranks the abilities --- as far as we can tell --- of every other species. . . . At first sight memory and imagination seem quite distinct: the first in concerned, after all, with what happened already whereas the second is all about what has not. But recent studies show that imagination is wholly dependent on memory, because memories are its building blocks. When we imagine something happening we root around in our memory and come up with experiences which seem likely to recur, then combine them, chop them, shake them and blend them until they come out as something entirely different." In my view, this is cannot be unrelated to the process of reconsolidation that I mentioned above and some of the biases that other writers have described (see September 20, 2011 post and June 12, 2011 post) whereby memories are altered.
A text box entitled "Remembering the Future" by Eleanor Maguire is inserted by Carter, which perceptively quotes Lewis Carroll's Alice in Wonderland: "It's a poor memory that only works backwards." Maguire cites an MRI study that found recalling past experiences and imagining future possible ones activated a network of brain regions in common including the hippocampus. She notes a new theory of 'scene reconstruction,' which allows for the internal rehearsal of events or scenes, which underpins the process of creating a simulated event. Maguire writes: "[I]n humans, the use of this scene reconstruction process goes far beyond simply predicting the future, to general evaluation of fitness for purpose and ultimately creativity. For example, a scriptwriter or novelist who is writing a passage in a film or book may play out the whole scene using their construction system, not with the idea of predicting the future, but instead for the purpose of evaluating its aesthetic suitability." This is the sort of discussion I was hoping to find in The Tell-Tale Brain (see previous post). What is missing from her discussion is the identification of the parts of the brain involved in imagination, although the text seems to identify the hippocampus as one candidate for assembling disparate memories. Also missing is the evolutionary basis for this ability. Obviously, the ability to plan for the future has survival value, and our planning capacity is lodged in the frontal cortex, where working memory occurs. The building blocks for understanding creative imagination are before us, and understanding a collateral capacity --- the capacity for deception, including self-deception --- by imaginatively rearranging memories and treating them as factual, when they are not, needs to be understood as well. Part of this is reflected in the previous discussions of mental biases. Carter notes that the subject of belief and non-belief is not unrelated to how the brain treats statements it believes to be true and those it believes to be false. Research, she says, shows that truth telling appears to be the default position for the human brain, and that telling lies involves extra cognitive effort. I am not sure this is entirely true, as bias mechanisms appear to be short-cuts for resolving conflicts in our memories.
By the end of Mapping the Brain, I wondered if this should have been the first book I ever read on the brain. Would I have better appreciated all the other material I have read on this subject if I had already read this book? I can't answer that, but studying Rita Carter's text after I had read these other books, many of which are discussed or mentioned in prior posts, was facilitated by my prior exposure to the subject. Either way, Mapping the Brain is a good overview and introduction to the brain and a good review as well.
Ramachandran's analogy that neuroscience's understanding of the brain is moving in the direction of establishing something akin to chemistry's periodic of table of elements is best left as a metaphor rather than a suggestion of equivalence (as I think the statement was intended). It is fair to say, like the periodic of table of elements, that the brain is organized, but it is not sequential in the same sense that the elements can be organized sequentially according to their atomic weight or related in their properties as part of one of 18 different groups. While thinking about this, it crossed my mind that evolutionary age would be one way of sequentially organizing the parts of the brain. Antonio Damasio did something like this in Self Comes to Mind (see April 8, 2011 post), describing the sequential evolution of the brain stem, the limbic system, and ultimately the cerebral cortex. But the brain is indeed very complex, as Carter notes in her closing paragraph, when she says that "today's mind voyagers are discovering a biological system of awe-inspiring complexity." One could also try to organize the parts of the brain sequentially, starting with a particular sensory input, and follow the connections to other parts of the brain to conscious awareness and action (or unconscious action, as the case may be) that ensues. In the end, however, that effort would not be particularly useful given the multi-layer network of sensory inputs that are processed simultaneously, including the presence of variable emotional reactions in connection with a particular sensory input that could stimulate a different behavioral outcome.
Both Carter and Ramachandran caused me to question a statement I made in a prior post (June 12, 2011 post) while discussing Michael Shermer's The Believing Brain. I wrote:
"I strongly suspect that if we dissected human brains and a network of connected neurons from a representative sample of humans, we would find a very high level of near identity among brains. There will be some differences due to DNA, and there will be some pathological differences as well, perhaps caused during embryonic development. But I believe that by and large we will find that human brains, neuron by neuron, are organized and folded and layered in substantially identical ways." There is substantial truth in my remark --- I did not say identical, but I did say "near identity" and "substantially identical." These words came at the risk of maybe overstating the case. Carter writes, "Human brains are constructed along fairly standard lines and so we all tend to see the world in a fairly standard way." And as I noted, there are differences due to DNA, pathological injury, and embryonic development. But I overlooked perhaps the largest exception --- experience (nurture) and its impact on memory -- and what is referred to as synaptic plasticity. And it is long-term memory -- enhanced by repeated experiences in some that others do not share --- that gives rise to our autobiographical self and what makes each one of us unique. So while we may "tend to see the world in a fairly standard way," Carter notes:
"Every brain constructs the world in a slightly different way from any other because every brain is different. The sight of an external object will vary from person to person because no two people have precisely the same number of motion cells, magenta-sensitive cells, or straight line cells. . . . An individual's view is formed both by their genes and by how their brain has been moulded by experience. Musicians, for instance, have brains which are physically different from others and which work differently when they play or hear music. . . . Extraordinary individual ways of seeing things may also arise from strange 'quirks' of brain development. Albert Einstein, for instance, had a very oddly constructed brain which might account for his astonishing insights into the nature of space and time."
Carter's treatment of language pretty much follows that of Ramachandran. And her treatment of memory restates much of what Antonio Damasio (see April 8, 2011 post) and Daniel Schacter (see September 20, 2011 post) discuss, but I still learned something new. For example, "Episodes that are destined for long-term memory are not lodged there right away. The process of laying them down permanently takes up to two years. Until then they are still fragile and may quite easily be wiped out. It is this replay from hippocampus to cortex and back again -- a process known as consolidation, that slowly turns fleeting impressions into long-term memories. . . Much of the hippocampal replay is thought to happen during sleep. Recordings from hippocampal cells show them engaging in a 'dialogue' with cortical cells, during which they signal one another, back and forth, in a call-and-reply formation. Some of this is known to take place during the 'quiet' phase of sleep, when dreaming, if it occurs at all, and is vague and instantly forgotten. Until memories are fully encoded in the cortex they are still fragile and may quite easily be wiped out. And even when they are established, they are not fixed. A memory is not, in fact, a recollection of an experience but the recollection of the last time you recalled the experience. Hence our memories are constantly changing and redeveloping. The process by which a memory changes is more or less the same as the consolidation process that lays it down for the first time. As we will see, each time we recall something, it is changed a little because it becomes mixed up with things that are happening in the present. Reconsolidation is a process by which this slightly altered memory effectively replaces the previous one, writing over it, so to speak, rather like re-recording over a rewritable DVD." I mentioned this phenomenon in the September 20, 2011 post discussing Daniel Schacter's discussion of the consistency bias, whereby the brain infers past beliefs from our current state and the reference to Joseph LeDoux's discussion of reconsolidation. Carter explains it better.
I also learned that not all memories are stored in cortical areas. While long-term memories are initially stored in the hippocampus, as described above, over the course of roughly two years they are transferred to the cortex and the hippocampus is no longer required for their retrieval. These memories are distributed in the same parts of the brain that encoded the original experience. So sounds are found in the auditory cortex, taste and skin sensory memories are found in the somatosensory cortex, and sight in the visual cortex. But procedural -- "how to" --- memories are stored outside of the cortex, in the cerebellum and putamen, and fear memories are stored in the amygdala.
Carter also addresses, albeit briefly, the subject of imagination, which I have touched on in several previous postings (see, for instance, July 30, 2011 post and May 22, 2011 post) and describes the connection to memory. "Our ability to conjure up scenarios which have not actually happened is prodigious. Imaginative capacity runs along a spectrum from the mundane skills required to envisage what your supper might taste like if you combined the onion, mushrooms, and left over chicken in the fridge with some curry sauce, through to the awe-inspiring visions of artists, writers, and excitable children. Even the humblest of these skills outranks the abilities --- as far as we can tell --- of every other species. . . . At first sight memory and imagination seem quite distinct: the first in concerned, after all, with what happened already whereas the second is all about what has not. But recent studies show that imagination is wholly dependent on memory, because memories are its building blocks. When we imagine something happening we root around in our memory and come up with experiences which seem likely to recur, then combine them, chop them, shake them and blend them until they come out as something entirely different." In my view, this is cannot be unrelated to the process of reconsolidation that I mentioned above and some of the biases that other writers have described (see September 20, 2011 post and June 12, 2011 post) whereby memories are altered.
A text box entitled "Remembering the Future" by Eleanor Maguire is inserted by Carter, which perceptively quotes Lewis Carroll's Alice in Wonderland: "It's a poor memory that only works backwards." Maguire cites an MRI study that found recalling past experiences and imagining future possible ones activated a network of brain regions in common including the hippocampus. She notes a new theory of 'scene reconstruction,' which allows for the internal rehearsal of events or scenes, which underpins the process of creating a simulated event. Maguire writes: "[I]n humans, the use of this scene reconstruction process goes far beyond simply predicting the future, to general evaluation of fitness for purpose and ultimately creativity. For example, a scriptwriter or novelist who is writing a passage in a film or book may play out the whole scene using their construction system, not with the idea of predicting the future, but instead for the purpose of evaluating its aesthetic suitability." This is the sort of discussion I was hoping to find in The Tell-Tale Brain (see previous post). What is missing from her discussion is the identification of the parts of the brain involved in imagination, although the text seems to identify the hippocampus as one candidate for assembling disparate memories. Also missing is the evolutionary basis for this ability. Obviously, the ability to plan for the future has survival value, and our planning capacity is lodged in the frontal cortex, where working memory occurs. The building blocks for understanding creative imagination are before us, and understanding a collateral capacity --- the capacity for deception, including self-deception --- by imaginatively rearranging memories and treating them as factual, when they are not, needs to be understood as well. Part of this is reflected in the previous discussions of mental biases. Carter notes that the subject of belief and non-belief is not unrelated to how the brain treats statements it believes to be true and those it believes to be false. Research, she says, shows that truth telling appears to be the default position for the human brain, and that telling lies involves extra cognitive effort. I am not sure this is entirely true, as bias mechanisms appear to be short-cuts for resolving conflicts in our memories.
Tuesday, October 25, 2011
V.S. Ramachandran, The Tell-Tale Brain (2011)
My original expectations for this book never materialized, but still there was much learned . From my cursory examination in the bookstore, I was expecting to learn something about the role of the brain in creating art, particularly storytelling, works of fiction and imagination. I noticed a couple of chapters on art and aesthetics, but these turned out to be ruminations and speculation on the role of the brain in appreciating visual arts. That is not to say these ruminations were without value, but only that I was expecting a different treatment of the subject.
Second, I knew that V.S. Ramachandran , one of the world's leading neuroscientists, promoted research findings about mirror neurons, a subject that was covered in the September 18, 2009 post discussing Marco Iacoboni's book, Mirroring People. Ramachandran, however, despite his disclaimer that mirror neurons do not explain everything about the brain, seems to suggest that they explain an awful lot: certainly a lot more than the subtitle of Iacoboni's book suggests --- empathy for others and how we are able to comprehend the actions and perhaps the intentions of others from their body movements. Ramachandran suggests that mirror neurons may also be key to understanding our own self-awareness: awareness of what our own mind is thinking. Regrettably, the proof is not yet there to support his surmises in this regard; too often Ramachandran says that this area of the brain is involved in such and such, and that area of the brain is known to be rich in mirror neurons, and with that association it might be the case that mirror neurons explain such and such. That is not to say he is wrong, but he may be more right than wrong when he says that mirror neurons do not explain everything.
Here is an example of what I just said. Ramachandran strongly believes that mirror neurons, while initially identified in monkeys, are an important piece in understanding human evolution. "[O]nly in humans do they seem to have developed to the point of being able to model aspects of others' minds rather than merely their actions. Inevitably this would have required the development of additional connections to allow a more sophisticated deployment of such circuits in complex social situations. . . It is difficult to overstate the importance of understanding mirror neurons and their function. They may well be central to social learning, imitation, and the cultural transmission of skills and attitudes --- perhaps even of the pressed-together sound clusters we call 'words.' By hyperdeveloping the mirror-neuron system, evolution in effect turned culture into the new genome. Armed with culture, humans could adapt to hostile new environments and figure out how to exploit formerly inaccessible or poisonous food sources in just one or two generations --- instead of the hundreds or thousands of generations such adaptations would have taken to accomplish through genetic evolution." This is an astonishing hypothesis, to borrow a phrase from Francis Crick. But Ramachandran strongly believes he is on to something because of the presence of mirror neurons located in certain parts of the human brain that are relatively unique to humans, in contrast to the apes, our nearest relative. Ramachandran is referring to Wernicke's area in the left temporal lobe (the area of the brain that is responsible for our comprehension of language -- where speech acquires meaning), the prefrontal cortex (an area responsible for decision-making and cognition, which includes the motor cortex where commands are sent to muscles for movement, and it includes Broca's area, which is responsible for speech), and the inferior parietal lobe (IPL). In humans, Ramachandran notes, the IPL evolved into two parts not found in apes --- the supramarginal gyrus (an area responsible for our ability to "visualize" words and action) and the angular gyrus (an area of the brain that Ramachandran says is connected to metaphor comprehension, but also finding a common denominator between two superficially dissimilar things). The genetic change that created these areas of the brain "rich in mirror neurons," surmises Ramachandran, "freed us from genetics by enhancing our ability to learn from one another" --- "liberat[ing] our brain from its Darwinian shackles, allowing the rapid spread of unique inventions" (tools, new words, constructing shelter, creating communities) that are at the foundation of culture. "Instead, increased sophistication of a single mechanism --- such as imitation and intention reading --- could explain the huge behavior gap between us and apes."
Ramachandran is a neuroscientist who has a wealth of clinical research observations about damage to specific areas of the brain and the consequences of that damage. And with that wealth, my appreciation for the role of specific areas of the brain and their connections to other areas of the brain during normal operations continued to grow. Other books, some of which are discussed in previous posts, have contributed to my appreciation, but Ramachandran's presentation in this book, including his drawings of the regions of the brain together with his glossary and specific case studies begins to put it all together. From a big picture point of view, with this book Ramachandran is pursuing the same subjects that Michael Gazzaniga pursued in examining what makes us "human" (see September 27, 2009 post) and that Antonio Damasio pursued in examining what creates our sense of self (see April 8, 2011 post). And Ramachandran contributes his own views on the origin of human language, a subject that was extensively reviewed in Christine Kenneally's The First Word (see August 31, 2009 post).
Let's discuss Ramanchandran on the evolution of language, because this is really the part of The Tell-Tale Brain that demonstrates what I have just said about this book. In discussing the evolution of language, Christine Kenneally reviews the views of Noam Chomsky (language is not the outcome of evolution, but is simply a built-in property of the brain), Stephen J. Gould (language initially evolved as a way to represent the world --- namely thinking about the world, and only later became a means of communication), and Steven Pinker (language is an instinct, an adaptation that is unique to humans that evolved specifically for communications purposes). Ramachandran does likewise, dismisses Chomsky quickly (his thesis cannot be tested), and then says that there is a grain of truth to both Gould and Pinker, but they just did not go far enough. For Ramanchandran, language did not evolve from some general mechanism for thinking, but neither did it evolve specifically for purposes of communication. What is innate and what evolved, says Ramachandran, is the competence to acquire rules of language. The actual acquisition of language occurs as a result of social interaction. Ramachandran believes that language was enabled by cross linkages in the brain between different motor maps (e.g. the area responsible for manual gestures and the area responsible for orafacial movements). Ramachandran calls this synkinesia ("together" "movement"), but he is borrowing from research on synesthesia, a brain phenomenon where senses are joined by cross-activation of two sensory maps. Thus what humans have is a built-in capacity to for translating gestures (movement) into words. The original "words," if you will, may have been grunts or other noises that accompanied a gesture (a proto-language). Synkinesia alone probably does not explain speech and language, but the human capacity for mimicry is critical as well, and hence the subject of mirror neurons enters the discussion of speech development, and again we return to the linkages between Broca's area, Wernicke's area, and the supramarginal gyrus and the angular gyrus in the IPL that enable what Ramachandran labels "cross-modal abstraction."
Ramachandran borrows from Gould the latter's concept of exaptation. An adaptation is an evolutionary response to natural selection. An exaptation is a refinement of an adaptation whereby a function is borrowed and used for a different function. Ramachandran believes that the IPL did not evolve for higher forms of abstraction such as giving names (words) to something, but evolved to provide hominids for refined interaction between vision and muscle and joint position while negotiating branches on tree top, a type of cross-modal abstraction. A subsequent exaptation was the development of these areas of the brain --- and their capacity for abstraction --- to develop tools and subassemblies of tools (e.g. an axehead and a suitably designed handle), says Ramachandran. He sees "a tantalizing resemblance" between the wielding of a tool made from composite parts and a full blown sentence including noun phrases and verbs. Speech, including syntax, emerged from the area of the brain that was key to tool manufacture, he speculates, and this became Broca's area. Add to that the areas of the parietal lobe (Wernicke's area and the IPL) and the human brain now has a language acquisition device. By the end of his discourse, Ramachandran concedes that he has been speculating on the evolution of language and thought, and he still has not resolved it, but he believes that it is not inconsistent with what neurologists know about patients who are damaged in these areas of the brain, and what we know about the evolution of other body parts. The problem is that language and abstraction are "software," and they can't be found in the fossil record that is all we have to understand what happened tens and hundreds of thousands of years ago. Unlike Christine Kenneally, Ramachandran does not discuss the debate over the FOXP2 gene and its possible connection to human language. Ramachandran asks, why were genes for language competence selected, but he does not illuminate what those genes might be., and perhaps that is because he recognizes that language is the outcome a several different modules in the brain, and there can be no single gene that would explain that fact.
There is much more to this book than just mirror neurons and the evolution of language, but there are discussions of memory, brain plasticity, the self, and free-will. Marco Iacoboni believes that, in view of research on mirror neurons and social behavior, the concepts of the self and free-will are blurred --- at least our Western sense of the individual is not as real as we sometimes think. (See September 18, 2009 post). Just how "free" and unique are we? he asks: Self and other are inextricably blended, says Iacoboni, and our behavior is subtly influenced by mirror neurons which produce automatic imitative influences based on what others are doing or saying. Iacoboni believes we have only "limited autonomy." Ramachandran does not touch this subject, but he does profess that humans have a sense of agency --- a desire to act and our belief in our ability to perform that act. Ramachandran says that there is evidence that the anterior cingulate in the frontal lobe is involved with wanting and intention. Damage to this area leads to apathy. The anterior cingulate, says Ramachandran, receives inputs from the parietal lobe, including the supramarginal gyrus, which as noted above, is involved with our ability to conjure up images of action (movement). These connections lead Ramachandran to believe there may be a neurological basis for free-will, signifying that it is not just a philosophical problem.
Ramachandran summarizes the current state of neuroscience with a comparison to chemistry: neuroscience is now at about the same stage that chemistry was in the 19th century, discovering the basic elements, grouping them into categories, and studying their interactions. As neuroscientists "map" the brain, they are "grouping their way toward the periodic table" of elements, but are not anywhere near atomic theory. As I noted in a previous post (see January 21, 2011 post and April 8, 2011 post), this is not fatal to the proposition that the era of skepticism is over. Ramachandran notes numerous experiments that remain to be started that would confirm one hypothesis or another.
And a final note. While Ramachandran failed to provide specific insight into how the brain creates art or fiction, on reflection, the elements of that mechanism may very well have been covered. We are, after all, talking about imagination, and the parts of the brain that enable abstraction, when combined with the parts of the brain that enable language (not just speech, but semantic content as well), when combined with the parts of the brain that enable us assemble things and to mimic what others do, must be involved in the creation of fiction and other forms of art that are the production of imagination.
Second, I knew that V.S. Ramachandran , one of the world's leading neuroscientists, promoted research findings about mirror neurons, a subject that was covered in the September 18, 2009 post discussing Marco Iacoboni's book, Mirroring People. Ramachandran, however, despite his disclaimer that mirror neurons do not explain everything about the brain, seems to suggest that they explain an awful lot: certainly a lot more than the subtitle of Iacoboni's book suggests --- empathy for others and how we are able to comprehend the actions and perhaps the intentions of others from their body movements. Ramachandran suggests that mirror neurons may also be key to understanding our own self-awareness: awareness of what our own mind is thinking. Regrettably, the proof is not yet there to support his surmises in this regard; too often Ramachandran says that this area of the brain is involved in such and such, and that area of the brain is known to be rich in mirror neurons, and with that association it might be the case that mirror neurons explain such and such. That is not to say he is wrong, but he may be more right than wrong when he says that mirror neurons do not explain everything.
Here is an example of what I just said. Ramachandran strongly believes that mirror neurons, while initially identified in monkeys, are an important piece in understanding human evolution. "[O]nly in humans do they seem to have developed to the point of being able to model aspects of others' minds rather than merely their actions. Inevitably this would have required the development of additional connections to allow a more sophisticated deployment of such circuits in complex social situations. . . It is difficult to overstate the importance of understanding mirror neurons and their function. They may well be central to social learning, imitation, and the cultural transmission of skills and attitudes --- perhaps even of the pressed-together sound clusters we call 'words.' By hyperdeveloping the mirror-neuron system, evolution in effect turned culture into the new genome. Armed with culture, humans could adapt to hostile new environments and figure out how to exploit formerly inaccessible or poisonous food sources in just one or two generations --- instead of the hundreds or thousands of generations such adaptations would have taken to accomplish through genetic evolution." This is an astonishing hypothesis, to borrow a phrase from Francis Crick. But Ramachandran strongly believes he is on to something because of the presence of mirror neurons located in certain parts of the human brain that are relatively unique to humans, in contrast to the apes, our nearest relative. Ramachandran is referring to Wernicke's area in the left temporal lobe (the area of the brain that is responsible for our comprehension of language -- where speech acquires meaning), the prefrontal cortex (an area responsible for decision-making and cognition, which includes the motor cortex where commands are sent to muscles for movement, and it includes Broca's area, which is responsible for speech), and the inferior parietal lobe (IPL). In humans, Ramachandran notes, the IPL evolved into two parts not found in apes --- the supramarginal gyrus (an area responsible for our ability to "visualize" words and action) and the angular gyrus (an area of the brain that Ramachandran says is connected to metaphor comprehension, but also finding a common denominator between two superficially dissimilar things). The genetic change that created these areas of the brain "rich in mirror neurons," surmises Ramachandran, "freed us from genetics by enhancing our ability to learn from one another" --- "liberat[ing] our brain from its Darwinian shackles, allowing the rapid spread of unique inventions" (tools, new words, constructing shelter, creating communities) that are at the foundation of culture. "Instead, increased sophistication of a single mechanism --- such as imitation and intention reading --- could explain the huge behavior gap between us and apes."
Ramachandran is a neuroscientist who has a wealth of clinical research observations about damage to specific areas of the brain and the consequences of that damage. And with that wealth, my appreciation for the role of specific areas of the brain and their connections to other areas of the brain during normal operations continued to grow. Other books, some of which are discussed in previous posts, have contributed to my appreciation, but Ramachandran's presentation in this book, including his drawings of the regions of the brain together with his glossary and specific case studies begins to put it all together. From a big picture point of view, with this book Ramachandran is pursuing the same subjects that Michael Gazzaniga pursued in examining what makes us "human" (see September 27, 2009 post) and that Antonio Damasio pursued in examining what creates our sense of self (see April 8, 2011 post). And Ramachandran contributes his own views on the origin of human language, a subject that was extensively reviewed in Christine Kenneally's The First Word (see August 31, 2009 post).
Let's discuss Ramanchandran on the evolution of language, because this is really the part of The Tell-Tale Brain that demonstrates what I have just said about this book. In discussing the evolution of language, Christine Kenneally reviews the views of Noam Chomsky (language is not the outcome of evolution, but is simply a built-in property of the brain), Stephen J. Gould (language initially evolved as a way to represent the world --- namely thinking about the world, and only later became a means of communication), and Steven Pinker (language is an instinct, an adaptation that is unique to humans that evolved specifically for communications purposes). Ramachandran does likewise, dismisses Chomsky quickly (his thesis cannot be tested), and then says that there is a grain of truth to both Gould and Pinker, but they just did not go far enough. For Ramanchandran, language did not evolve from some general mechanism for thinking, but neither did it evolve specifically for purposes of communication. What is innate and what evolved, says Ramachandran, is the competence to acquire rules of language. The actual acquisition of language occurs as a result of social interaction. Ramachandran believes that language was enabled by cross linkages in the brain between different motor maps (e.g. the area responsible for manual gestures and the area responsible for orafacial movements). Ramachandran calls this synkinesia ("together" "movement"), but he is borrowing from research on synesthesia, a brain phenomenon where senses are joined by cross-activation of two sensory maps. Thus what humans have is a built-in capacity to for translating gestures (movement) into words. The original "words," if you will, may have been grunts or other noises that accompanied a gesture (a proto-language). Synkinesia alone probably does not explain speech and language, but the human capacity for mimicry is critical as well, and hence the subject of mirror neurons enters the discussion of speech development, and again we return to the linkages between Broca's area, Wernicke's area, and the supramarginal gyrus and the angular gyrus in the IPL that enable what Ramachandran labels "cross-modal abstraction."
Ramachandran borrows from Gould the latter's concept of exaptation. An adaptation is an evolutionary response to natural selection. An exaptation is a refinement of an adaptation whereby a function is borrowed and used for a different function. Ramachandran believes that the IPL did not evolve for higher forms of abstraction such as giving names (words) to something, but evolved to provide hominids for refined interaction between vision and muscle and joint position while negotiating branches on tree top, a type of cross-modal abstraction. A subsequent exaptation was the development of these areas of the brain --- and their capacity for abstraction --- to develop tools and subassemblies of tools (e.g. an axehead and a suitably designed handle), says Ramachandran. He sees "a tantalizing resemblance" between the wielding of a tool made from composite parts and a full blown sentence including noun phrases and verbs. Speech, including syntax, emerged from the area of the brain that was key to tool manufacture, he speculates, and this became Broca's area. Add to that the areas of the parietal lobe (Wernicke's area and the IPL) and the human brain now has a language acquisition device. By the end of his discourse, Ramachandran concedes that he has been speculating on the evolution of language and thought, and he still has not resolved it, but he believes that it is not inconsistent with what neurologists know about patients who are damaged in these areas of the brain, and what we know about the evolution of other body parts. The problem is that language and abstraction are "software," and they can't be found in the fossil record that is all we have to understand what happened tens and hundreds of thousands of years ago. Unlike Christine Kenneally, Ramachandran does not discuss the debate over the FOXP2 gene and its possible connection to human language. Ramachandran asks, why were genes for language competence selected, but he does not illuminate what those genes might be., and perhaps that is because he recognizes that language is the outcome a several different modules in the brain, and there can be no single gene that would explain that fact.
There is much more to this book than just mirror neurons and the evolution of language, but there are discussions of memory, brain plasticity, the self, and free-will. Marco Iacoboni believes that, in view of research on mirror neurons and social behavior, the concepts of the self and free-will are blurred --- at least our Western sense of the individual is not as real as we sometimes think. (See September 18, 2009 post). Just how "free" and unique are we? he asks: Self and other are inextricably blended, says Iacoboni, and our behavior is subtly influenced by mirror neurons which produce automatic imitative influences based on what others are doing or saying. Iacoboni believes we have only "limited autonomy." Ramachandran does not touch this subject, but he does profess that humans have a sense of agency --- a desire to act and our belief in our ability to perform that act. Ramachandran says that there is evidence that the anterior cingulate in the frontal lobe is involved with wanting and intention. Damage to this area leads to apathy. The anterior cingulate, says Ramachandran, receives inputs from the parietal lobe, including the supramarginal gyrus, which as noted above, is involved with our ability to conjure up images of action (movement). These connections lead Ramachandran to believe there may be a neurological basis for free-will, signifying that it is not just a philosophical problem.
Ramachandran summarizes the current state of neuroscience with a comparison to chemistry: neuroscience is now at about the same stage that chemistry was in the 19th century, discovering the basic elements, grouping them into categories, and studying their interactions. As neuroscientists "map" the brain, they are "grouping their way toward the periodic table" of elements, but are not anywhere near atomic theory. As I noted in a previous post (see January 21, 2011 post and April 8, 2011 post), this is not fatal to the proposition that the era of skepticism is over. Ramachandran notes numerous experiments that remain to be started that would confirm one hypothesis or another.
And a final note. While Ramachandran failed to provide specific insight into how the brain creates art or fiction, on reflection, the elements of that mechanism may very well have been covered. We are, after all, talking about imagination, and the parts of the brain that enable abstraction, when combined with the parts of the brain that enable language (not just speech, but semantic content as well), when combined with the parts of the brain that enable us assemble things and to mimic what others do, must be involved in the creation of fiction and other forms of art that are the production of imagination.
Tuesday, September 20, 2011
Daniel Schacter, The Seven Sins of Memory (2001)
I started this blog, in small part, because I could not always recall when I read a book and what I got out of it. I thought about making notes in a notebook, like I did in college, and thought why not a digital notebook? The subject memory has continuously popped up in my postings, as the previous post recalls. In The Seven Sins of Memory, Harvard psychologist Daniel Schacter explains why I can't recall when I read a particular book and other failings of the human memory. And it's not all bad. In fact, Schacter says it's OK to forget. It's common. It's natural.
A clever title. Like the "seven deadly sins," the title is not an allusion to sinful behavior. It is a reference to our vulnerabilities and imperfections. Seven imperfections of memory: transience (memory that fades with the passage of time); absent-mindedness (rapid forgetting due to attentional lapses); blocking (hopefully a merely temporal phenomenon, like the name on the tip of your tongue that you can't remember); misattribution (mistaken identification); suggestibility (tendency to incorporate misleading information from external sources by suggestion into personal recollections); bias (five tendencies in which we generalize to reduce dissonance, reconstruct the past to fit the present, organize and regulate our mental life, and categorize; and persistence (remembering things we really want to forget).
All of us are familiar with and have experienced most, if not all of these imperfections of our memory. Some memories are encoded and "stick." Eric Kandel and others have described to us much of the biological basis about why we understand certain memories stay around longer than others --- long term potentiation. But not all memories stick. Some memories disappear immediately (absent-mindedness, because encoding fails due to divided attention); other memories stick, but are not retrievable --- sometimes for reasons we still do not fully understand --- but sometimes because we have little opportunity ever to recall a personal experience or piece of knowledge again and we forget(transience). And some memories are simply not accurate --- misidentification due to the inability to have specific recall of people or events that we are generally familiar with, or revised because external sources of information suggest to us that something different occurred, or biasing influences.
The bias influence is something we are already familiar with from Michael Shermer's book, The Believing Brain. (See June 12, 2011 post). What Shermer called the "confirmatory bias," Schacter refers to as the "consistency bias," where we infer past beliefs from our current state. This bias promotes psychological stability, perhaps avoiding cognitive dissonance. Similarly, hindsight bias, Schacter says, is ubiquitous, and reconstructs past to fit the present. What Shermer called the "self justification" bias, Schacter labels the "egocentric bias" that gives more credence to our own recollection of events --- reflecting the role of "self" in organizing and regulating our mental life. Studies show that when the mind encodes new information by relating it to the self, subsequent memory improves. Finally, the "stereotypical bias" reflects the minds tendency to categorize. What Shermer failed to address is the neurobiological basis for these biases. Schacter tries to address this, and, not surprisingly, calls on research by Michael Gazzaniga (see September 27, 2009 post) to explain it. The source of bias probably begins in the left hemisphere of the brain, which is adept at coming up with explanations and rationalizations for situations. This is the region where Gazzaniga's "interpreter" resides, the area responsible for language and symbols. The left hemisphere is responsible for inferences and generalizations to relate past and present. It draws on general knowledge and past experience to bring order to our psychological world. In contrast, the right hemisphere is where images and spatial location are prominent. The right hemisphere has a proclivity to respond on a literal basis to our environment, and acts as a check on the generalization of the left hemisphere. The left hemisphere probably contributes to consistency bias, hindsight bias, and egocentric bias. The left hemisphere is where our storytelling capacity resides. It is also where memories may be strengthened. Thinking and talking about our experiences changes the likelihood of subsequent remembering, reducing transience: elaborate encoding occurs to create memory.
I am reminded of an article by Joseph LeDoux of New York University in The Scientist back in 2009, entitled "Manipulating Memory." LeDoux reports on work that supports a theory of "reconsolidation" whereby memories are updated and influenced by new information. In other words, once a memory is recalled it is in a fragile state, and iit s susceptible to disruption by the very act of remembering so that what is "remembered" is not the same as what was experienced at the time of the event recalled. Several of Schacter's "sins" seem to support this view of human memory that it is neither fixed nor permanent.
These vulnerabilities of memory are not design flaws. They are likely by-products of of adaptive features of memory that have, in the long-run, served human memory well. Schacter reminds me of Antonio Damasio's reliance on the concept of homeostasis (see April 8, 2011 post) when he refers to the brain's "trade-off" between reducing the need to access information that is not needed or has not been needed and the cost of forgetting. The brain has adapted to an equilibrium condition. Transience occurs because there is little utility in storing unimportant, noncurrent information. Retrieval of "too much information" (data overload) has negative consequences and sacrifices abstract thinking. The brain does go on to autopilot --- repetitive events are handled by automatic processes, freeing up the brain's ability to devote attention to things with consequences; as a consequence occasional absent-minded errors occur when the mind is focused on something else, a small cost for the larger benefit of being able to pay attention. Memory sometimes operates because cues trigger recall. Contrary to some popular philosophers, David Hume's associationism is not dead. (See February 27, 2011 post).
The ability to record (encode) the gist of what happens and not every detail is a strength of memory, says Schacter. This capacity is fundamental to categorizing and comprehending and allows us to generalize across experiences without dwelling on details. Misattribution (false recognition) is probably a price we pay for the benefit of generalization. Generalizing, as discussed above, also leads to biases. Some features of memory are adaptations in evolutionary terms -- larger hippocampuses that facilitate finding stored food, and the amygdala that plays a role in emotional conditioning (contributing to the sin of "persistence"). But several features of our memory are unintended by-products of an existing feature or functionality of the brain. Schacter postulates that aspects of memory are what Stephen J. Gould referred to as "exaptations," features co-opted from an existing function that enhance fitness, but were not built by natural selection. Biases, Schacter concludes, are an incidental by-product of general knowledge and beliefs; blocking, absent-mindedness, misattribution, and suggestibility are exaptations of a memory system that does not routinely preserve all details required to specify the source of an experience.
There are practical concerns that arise from the learning in this book. The "sins" of misattribution, suggestibility, and bias all have implications for our justice system -- particularly criminal justice. Eyewitness misidentification, false confessions, witnesses influenced by suggestive questioning that retrieves a memory that does not match the actual experience are particularly worrisome. Law enforcement has taken notice and is learning from this research.
That we recognize that human memory is vulnerable, and that it is neither fixed nor permanent, informs us with respect to our history as well. While there are histories that are literally revisionist histories --- Schacter cites George Orwell's 1984 where a totalitarian government deliberately revises the past to suit the present --- our oral and written histories are known to have been revised to suit a current agenda. Knowing that "gospels" are the product of human writers, editors and redacters, it is difficult to understand why some have difficulty in acknowledging that the stories in these gospels suffer from the same vulnerabilities that human memory suffers. There are undoubtedly other psychological states that produce such difficulty.
A clever title. Like the "seven deadly sins," the title is not an allusion to sinful behavior. It is a reference to our vulnerabilities and imperfections. Seven imperfections of memory: transience (memory that fades with the passage of time); absent-mindedness (rapid forgetting due to attentional lapses); blocking (hopefully a merely temporal phenomenon, like the name on the tip of your tongue that you can't remember); misattribution (mistaken identification); suggestibility (tendency to incorporate misleading information from external sources by suggestion into personal recollections); bias (five tendencies in which we generalize to reduce dissonance, reconstruct the past to fit the present, organize and regulate our mental life, and categorize; and persistence (remembering things we really want to forget).
All of us are familiar with and have experienced most, if not all of these imperfections of our memory. Some memories are encoded and "stick." Eric Kandel and others have described to us much of the biological basis about why we understand certain memories stay around longer than others --- long term potentiation. But not all memories stick. Some memories disappear immediately (absent-mindedness, because encoding fails due to divided attention); other memories stick, but are not retrievable --- sometimes for reasons we still do not fully understand --- but sometimes because we have little opportunity ever to recall a personal experience or piece of knowledge again and we forget(transience). And some memories are simply not accurate --- misidentification due to the inability to have specific recall of people or events that we are generally familiar with, or revised because external sources of information suggest to us that something different occurred, or biasing influences.
The bias influence is something we are already familiar with from Michael Shermer's book, The Believing Brain. (See June 12, 2011 post). What Shermer called the "confirmatory bias," Schacter refers to as the "consistency bias," where we infer past beliefs from our current state. This bias promotes psychological stability, perhaps avoiding cognitive dissonance. Similarly, hindsight bias, Schacter says, is ubiquitous, and reconstructs past to fit the present. What Shermer called the "self justification" bias, Schacter labels the "egocentric bias" that gives more credence to our own recollection of events --- reflecting the role of "self" in organizing and regulating our mental life. Studies show that when the mind encodes new information by relating it to the self, subsequent memory improves. Finally, the "stereotypical bias" reflects the minds tendency to categorize. What Shermer failed to address is the neurobiological basis for these biases. Schacter tries to address this, and, not surprisingly, calls on research by Michael Gazzaniga (see September 27, 2009 post) to explain it. The source of bias probably begins in the left hemisphere of the brain, which is adept at coming up with explanations and rationalizations for situations. This is the region where Gazzaniga's "interpreter" resides, the area responsible for language and symbols. The left hemisphere is responsible for inferences and generalizations to relate past and present. It draws on general knowledge and past experience to bring order to our psychological world. In contrast, the right hemisphere is where images and spatial location are prominent. The right hemisphere has a proclivity to respond on a literal basis to our environment, and acts as a check on the generalization of the left hemisphere. The left hemisphere probably contributes to consistency bias, hindsight bias, and egocentric bias. The left hemisphere is where our storytelling capacity resides. It is also where memories may be strengthened. Thinking and talking about our experiences changes the likelihood of subsequent remembering, reducing transience: elaborate encoding occurs to create memory.
I am reminded of an article by Joseph LeDoux of New York University in The Scientist back in 2009, entitled "Manipulating Memory." LeDoux reports on work that supports a theory of "reconsolidation" whereby memories are updated and influenced by new information. In other words, once a memory is recalled it is in a fragile state, and iit s susceptible to disruption by the very act of remembering so that what is "remembered" is not the same as what was experienced at the time of the event recalled. Several of Schacter's "sins" seem to support this view of human memory that it is neither fixed nor permanent.
These vulnerabilities of memory are not design flaws. They are likely by-products of of adaptive features of memory that have, in the long-run, served human memory well. Schacter reminds me of Antonio Damasio's reliance on the concept of homeostasis (see April 8, 2011 post) when he refers to the brain's "trade-off" between reducing the need to access information that is not needed or has not been needed and the cost of forgetting. The brain has adapted to an equilibrium condition. Transience occurs because there is little utility in storing unimportant, noncurrent information. Retrieval of "too much information" (data overload) has negative consequences and sacrifices abstract thinking. The brain does go on to autopilot --- repetitive events are handled by automatic processes, freeing up the brain's ability to devote attention to things with consequences; as a consequence occasional absent-minded errors occur when the mind is focused on something else, a small cost for the larger benefit of being able to pay attention. Memory sometimes operates because cues trigger recall. Contrary to some popular philosophers, David Hume's associationism is not dead. (See February 27, 2011 post).
The ability to record (encode) the gist of what happens and not every detail is a strength of memory, says Schacter. This capacity is fundamental to categorizing and comprehending and allows us to generalize across experiences without dwelling on details. Misattribution (false recognition) is probably a price we pay for the benefit of generalization. Generalizing, as discussed above, also leads to biases. Some features of memory are adaptations in evolutionary terms -- larger hippocampuses that facilitate finding stored food, and the amygdala that plays a role in emotional conditioning (contributing to the sin of "persistence"). But several features of our memory are unintended by-products of an existing feature or functionality of the brain. Schacter postulates that aspects of memory are what Stephen J. Gould referred to as "exaptations," features co-opted from an existing function that enhance fitness, but were not built by natural selection. Biases, Schacter concludes, are an incidental by-product of general knowledge and beliefs; blocking, absent-mindedness, misattribution, and suggestibility are exaptations of a memory system that does not routinely preserve all details required to specify the source of an experience.
There are practical concerns that arise from the learning in this book. The "sins" of misattribution, suggestibility, and bias all have implications for our justice system -- particularly criminal justice. Eyewitness misidentification, false confessions, witnesses influenced by suggestive questioning that retrieves a memory that does not match the actual experience are particularly worrisome. Law enforcement has taken notice and is learning from this research.
That we recognize that human memory is vulnerable, and that it is neither fixed nor permanent, informs us with respect to our history as well. While there are histories that are literally revisionist histories --- Schacter cites George Orwell's 1984 where a totalitarian government deliberately revises the past to suit the present --- our oral and written histories are known to have been revised to suit a current agenda. Knowing that "gospels" are the product of human writers, editors and redacters, it is difficult to understand why some have difficulty in acknowledging that the stories in these gospels suffer from the same vulnerabilities that human memory suffers. There are undoubtedly other psychological states that produce such difficulty.
Sunday, August 28, 2011
William Shakespeare, King Lear (1607)
The most powerful of human senses is vision. For this reason, it is perhaps not surprising that that some of the most powerful stories of the human condition conceived by human storytellers involve tales of blindness. King Lear is such a story.
Ironically, one of the greatest fictional stories of the human condition -- the Genesis story (chs. 1-3) --- connects The Fall, not to blindness, but to sightedness. As Robert Alter explains in his translation of Genesis, succumbing to desire and "lust," the primordial humans, Adam and Eve, ate the fruit of a tree ('that it was lust to the eyes and the tree was lovely to look at") in the Garden of Eden, "[a]nd the eyes of the two [Adam and Eve] were opened, and they knew they were naked, and they sewed fig leaves and they made themselves loincloths." Through sightedness, they acquired knowledge: by the word of the serpent, knowledge of good and evil. But that is not the entire story. Sightedness is a consequence of failing to observe a god's commandment ("You shall not eat from it, and you shall not touch it lest you die.") With their condition of sightedness, Adam and Eve are expelled from a world of perfection and forced to till the soil to survive in a world of imperfection and scarce resources. Generations of jealousy, murder, and deception ensue. Hence, The Fall.
King Lear flips the Genesis story. Lear is, like much of mankind, fallen. Among his catalogue of failings, he solicits flattery. One who flatters offers insincere praise. One who solicits flattery is arguably involved in a pleasing form of self-deception. And self-deception is a form of blindness, the condition of which Lear suffers. Soliciting flattery from his two eldest daughters, Lear is pleased, and rewards them with a share of his kingdom as he prepares to withdraw from ruling. His youngest daughter, Cordelia, offers him only a sincere expression of her undying love, but not flattery. Lear cannot see her genuine love. Because of Lear's blindness, Cordelia is expelled from Lear's kingdom and flees to France. We have Genesis inverted: Man expelled from god's kingdom because he failed to observe the commandment of a "superior" and consequently, he "sees"; generations of deception ensue his failure to please his superior; by contrast, in Lear, we have a man who controls a human kingdom suffers a blinding, deceptive condition in the form of self-flattery, and expels his daughter, who seems wiser in her young years than her elder father, from his kingdom because she fails to please her father.
The Earl of Kent endeavors to salvage the relationship before it is too late, but Lear tells Kent, "Out of my sight," and Kent responds, "See better Lear, and let me still remain the true blank of thine eye." But Lear cannot distinguish genuine love from insincere forms of adulation. Oblivious to the conspiracy of his family and others around him, murder and suicide follow. In Genesis, blindness is a blessing; in King Lear, it is a curse.
The parallel story within the story of the Earl of Gloucester features a father who cares for his bastard son and is deceived by his true son, Edmund, to believe that the bastard Edgar is out to kill him. Gloucester takes up the cause of Lear and is declared a traitor by Lear's eldest daughters and their husbands. One husband, the Duke of Cornwall, gouges out both of Gloucester's eyes, leaving him completely blind. Where King Lear is the blind victim of self-deception, Gloucester is the blind victim of another's deception.
For both of these "blind" elders, Shakespeare awakens them with their other senses. Gloucester is offered assistance by a man who has been a tenant on his properties. Gloucester rejects the aid, and the tenant explains, "You cannot see your way." Gloucester replies, "I have no way and therefore want no eyes. I stumbled when I saw." We never heard a similar admission from Adam in Genesis. Remorseful that he mistakenly believed his bastard son Edgar intended him harm, Gloucester adds, "O dear son Edgar, the food of thy abused father's wrath! Might I but live to see in thy touch, I'd say I had eyes again."
Lear later says to Gloucester, "Read," and Gloucester responds, "With the case of eyes?." Lear: "Oho, are you there with me? No eyes in your head nor no money in your purse? Your eyes are in a heavy case, your purse in a light, yet you see how this world goes." Gloucester: "I see it feelingly." Lear: "What, art mad? A man may see how this world goes with no eyes. Look with thine ears. See how yond justice rails upon yond simple thief. . . . Get these glass eyes, And like a scurvy politician seem to see things thou dost not."
Sightedness leads the human condition to blindness, and to recover, survive and find justice we are compelled to rely on other senses -- touch, hearing, and feeling. Despite our blindness, we can still "see how this world goes." Gloucester dies, as do Lear's daughters, including Cordelia, one son-in-law, Cornwall, and Gloucester's son Edmund, and ultimately Lear succumbs. The survivors include Gloucester's bastard son Edgar, and the Earl of Kent, who successfully concealed himself from Lear and others in order to survive. There is no happy resolution here, but the decent characters who suffered not from blindness or self-deception do live to tell the tale.
So which is an affliction: sightedness or blindness? In Jose Saramago's novel Blindness, it is blindness that is an affliction and it is sightedness that is able influence justice and offer hope. The answer to the question will depend on the story an author wants to tell. For Shakespeare, blindness is likewise the affliction, but it is our other senses that enable us to see when our sight cannot. It should be no surprise that our greatest stories revolve around an appreciation and explication of the senses and feelings, which are at the core of our self. (See April 8, 2011 post (Damasio) and February 27, 2011 post (Hume)).
Ironically, one of the greatest fictional stories of the human condition -- the Genesis story (chs. 1-3) --- connects The Fall, not to blindness, but to sightedness. As Robert Alter explains in his translation of Genesis, succumbing to desire and "lust," the primordial humans, Adam and Eve, ate the fruit of a tree ('that it was lust to the eyes and the tree was lovely to look at") in the Garden of Eden, "[a]nd the eyes of the two [Adam and Eve] were opened, and they knew they were naked, and they sewed fig leaves and they made themselves loincloths." Through sightedness, they acquired knowledge: by the word of the serpent, knowledge of good and evil. But that is not the entire story. Sightedness is a consequence of failing to observe a god's commandment ("You shall not eat from it, and you shall not touch it lest you die.") With their condition of sightedness, Adam and Eve are expelled from a world of perfection and forced to till the soil to survive in a world of imperfection and scarce resources. Generations of jealousy, murder, and deception ensue. Hence, The Fall.
King Lear flips the Genesis story. Lear is, like much of mankind, fallen. Among his catalogue of failings, he solicits flattery. One who flatters offers insincere praise. One who solicits flattery is arguably involved in a pleasing form of self-deception. And self-deception is a form of blindness, the condition of which Lear suffers. Soliciting flattery from his two eldest daughters, Lear is pleased, and rewards them with a share of his kingdom as he prepares to withdraw from ruling. His youngest daughter, Cordelia, offers him only a sincere expression of her undying love, but not flattery. Lear cannot see her genuine love. Because of Lear's blindness, Cordelia is expelled from Lear's kingdom and flees to France. We have Genesis inverted: Man expelled from god's kingdom because he failed to observe the commandment of a "superior" and consequently, he "sees"; generations of deception ensue his failure to please his superior; by contrast, in Lear, we have a man who controls a human kingdom suffers a blinding, deceptive condition in the form of self-flattery, and expels his daughter, who seems wiser in her young years than her elder father, from his kingdom because she fails to please her father.
The Earl of Kent endeavors to salvage the relationship before it is too late, but Lear tells Kent, "Out of my sight," and Kent responds, "See better Lear, and let me still remain the true blank of thine eye." But Lear cannot distinguish genuine love from insincere forms of adulation. Oblivious to the conspiracy of his family and others around him, murder and suicide follow. In Genesis, blindness is a blessing; in King Lear, it is a curse.
The parallel story within the story of the Earl of Gloucester features a father who cares for his bastard son and is deceived by his true son, Edmund, to believe that the bastard Edgar is out to kill him. Gloucester takes up the cause of Lear and is declared a traitor by Lear's eldest daughters and their husbands. One husband, the Duke of Cornwall, gouges out both of Gloucester's eyes, leaving him completely blind. Where King Lear is the blind victim of self-deception, Gloucester is the blind victim of another's deception.
For both of these "blind" elders, Shakespeare awakens them with their other senses. Gloucester is offered assistance by a man who has been a tenant on his properties. Gloucester rejects the aid, and the tenant explains, "You cannot see your way." Gloucester replies, "I have no way and therefore want no eyes. I stumbled when I saw." We never heard a similar admission from Adam in Genesis. Remorseful that he mistakenly believed his bastard son Edgar intended him harm, Gloucester adds, "O dear son Edgar, the food of thy abused father's wrath! Might I but live to see in thy touch, I'd say I had eyes again."
Lear later says to Gloucester, "Read," and Gloucester responds, "With the case of eyes?." Lear: "Oho, are you there with me? No eyes in your head nor no money in your purse? Your eyes are in a heavy case, your purse in a light, yet you see how this world goes." Gloucester: "I see it feelingly." Lear: "What, art mad? A man may see how this world goes with no eyes. Look with thine ears. See how yond justice rails upon yond simple thief. . . . Get these glass eyes, And like a scurvy politician seem to see things thou dost not."
Sightedness leads the human condition to blindness, and to recover, survive and find justice we are compelled to rely on other senses -- touch, hearing, and feeling. Despite our blindness, we can still "see how this world goes." Gloucester dies, as do Lear's daughters, including Cordelia, one son-in-law, Cornwall, and Gloucester's son Edmund, and ultimately Lear succumbs. The survivors include Gloucester's bastard son Edgar, and the Earl of Kent, who successfully concealed himself from Lear and others in order to survive. There is no happy resolution here, but the decent characters who suffered not from blindness or self-deception do live to tell the tale.
So which is an affliction: sightedness or blindness? In Jose Saramago's novel Blindness, it is blindness that is an affliction and it is sightedness that is able influence justice and offer hope. The answer to the question will depend on the story an author wants to tell. For Shakespeare, blindness is likewise the affliction, but it is our other senses that enable us to see when our sight cannot. It should be no surprise that our greatest stories revolve around an appreciation and explication of the senses and feelings, which are at the core of our self. (See April 8, 2011 post (Damasio) and February 27, 2011 post (Hume)).
Monday, August 15, 2011
James Gleick, The Information (2011)
If there is one book that touches so many of the posts in this blog, it is James Gleick's The Information. Covering much of the territory as the two books covered by the first two posts --- Seth Lloyd's Programming the Universe (August 17, 2009 post) and Charles Seife's Decoding the Universe (August 23, 2009 post) --- including the physical nature of information, the relevance of the laws of thermodynamics to information theory, as well as the exploits of World War II codebreakers and the story of information theory developed by Claude Shannon and others --- Gleick also covers the history of information storage and transmission from the beginning of recorded history to Google. And there is even a tip of the hat to John Banville's The Infinities, (see March 28, 2010 post, where I noted the novel's connections to Lloyd and Seife).
Much of The Information covers the history of the transmission of information from Sumerian times to the present. The media evolves from markings in the earth, to stone tablets, to paper wrapped in scrolls, to paper bound in book form, to rhythmic pulses of drums, to pulses of energy over electrical wire,to pulses of energy through the air. With Claude Shannon's revolutionary 1949 paper on a mathematical theory of communication, whose purpose was to address an engineering problem of "reproducing at one point either exactly or approximately a message selected at another point," the way we look at information transmission changed. As described in the August 23, 2009 post on Charles Seife's Decoding the Universe, Shannon understood that information could be measured and quantized, which would enable him to determine how much information could be transmitted through a given channel of transmission. Semantics and meaning are irrelevant to this exercise, but the measurements were extremely useful in solving various communications problems associated with telephone communications at the time and has likewise been useful in developing greater bandwidth so more information is capable of transmission at a given time from one point to another. Shannon also understood that information was physical and was subject to the laws of thermodynamics just as other physical features of the universe, and particularly the second law pertaining to entropy. (See August 17, 2009 post). Shannon further addressed the problem of "noise" in the communication channel that corrupted or interfered with information in transmission, and a mathematical means for filtering out that noise to determine probabilistically that the information received was the same as the information sent.
I have previously complained that whoever said that entropy refers to disorder did the world a disservice. (See August 17, 2009 post), and Gleick confirms that much confusion has ensued over the centuries in our discourse over the "second law" of thermodynamics because of the way entropy has been characterized. For those looking for some clarity about the principle of entropy, Gleick is worth reading. As initially conceived, entropy was a measure of the unavailability of energy for work because of dissipation. It referred to a "thermodynamic condition," where previously separate hot and cold bodies (could be a liquid or gas) generated steam that could be converted to energy for work, but once the hot and cold bodies mixed, the mixture achieved a uniform temperature and the amount of energy in steam dissipated making it unavailable for work. The "thermodynamic condition" that previously existed was said to have "dissipated," and there was no more energy available for work. The phrase "disorder" entered the picture because the previous thermodynamic condition where hot and cold bodies were separated and were capable of generating energy for work was considered "orderly," and the homogeneous mixture that was not capable of generating energy for work was considered "disorderly." The second law of thermodynamics stands for the proposition that the universe "tends" to flow from the orderly to the disorderly. Ironically, the "orderly" was viewed as a "less likely" macrostate, and the "disorderly" was viewed as a "more likely" macrostate. Probability theory therefore enters this discussion, and what is more probable is a homogeneous state where we are less likely to find separate distinct states.
Shannon's insight was that entropy was relevant to all dynamic systems, not just thermodynamics. To the physicist, entropy is a measurement of uncertainty about the state of a physical system. To the information theorist, entropy is a measure of uncertainty about a message, where it is less clear that the message that was transmitted is the same as the message that was received. Ironically, notes Gleick, humans, contrary to physical laws, seem bent on curbing entropy, making the environment in which they live, more orderly. We build things; we compile; we categorize; we separate. As Schrodinger noted, living things feed on negative entropy. The second law contemplates a closed system, and earth is not a closed system. Life feeds upon energy and negative entropy leaking into the earth's system. Similarly, humans have proven creative in dealing with probabilities and discerning information from communications that are not certain in order to make messages more certain and information theory provides us tools to do just that.
In contrast to Seth Lloyd and Charles Seife's works on the same subject, Gleick spends more time chronicling the technological development of information transmission. As I read on, I found myself thinking about a different subject to which Gleick gives only passing attention: memory. The subject of memory has been a continuous visitor to this blog, (See posts of September 9, 2010, September 28, 2010, November 27, 2010, and April 8, 2011). We tend to think of memory in terms of an information storage device. A 500 page book stores two million bits of information. A computer's hard drive or a CD-ROM store vastly more bits of information. These devices do not store words or images. They store information that encodes for words or images, but they also contain an electrical means for retrieving those images and words that are encoded. Thus a system of retrieving memory is essential to memory, otherwise it has no utility. This is entirely consistent with the description of the human brain's "architecture of memory" as described by Antonio Damasio. (See April 8, 2011 post). By Damasio's reckoning, the architecture of memory he describes evolved because of storage capacity limitations on our ability to retain images of prior events. Instead of files of memories of images and words, memory is found in the connections between cells in the brain. (See post of November 27, 2010). Shannon's research influenced the development of cognitive psychology, Gleick reports, because it became useful in understanding the limitations on our capacity to receive and store information, short-term and long-term memory, pattern recognition, attention, and problem solving.
Gleick does briefly allude to another subject that has received attention in prior posts: the human mind's capacity for storytelling and providing an explanation for what we experience, along the lines described by Michael Gazzaniga in Human. (See May 22, 2011 post and June 12 and June 28, 2011 posts). Storytelling has to be linked to memory formation and retrieval. Recording information, --- on sticks, on walls of caves, whatever --- says Gleick, "served as aids to memory." Homer's poetry, composed and sung in a mnemonic meter, "served first and foremost as an aid to memory." I think storytelling evolved in part to preserve our memory, but the irony is that those same stories can lead to distortions of the memory we try to preserve. Information is corrupted and does not copy accurately.
We have heard about this same sort of phenomenon in the context of the genome. (See November 27, 2010 post). The ultimate information storage device is the cell. The cell stores genetic material --- genes --- each of which is comprised of bits of information. At some point in evolutionary history, the means for communicating the information stored in the cell through replication became possible. Information contained in one information storage device was moved to another information storage device. Gleick quotes George Gamow: "The nucleus of a living cell is a storehouse of information," adding that it is a transmitter of information from which stems the continuity of life. Gamow described the study of genetics as the study of "the language of the cells." Matt Ridley (see November 27, 2010 post) would agree. When biologists discovered redundancy in the codons of the cell, they realized it was nature's way of dealing with "noise" in the transmission of information by providing tolerance for errors in transmission.
At some point in human evolution, external storage of information became important for survival. Gleick describes some of the earliest known examples of external information storage --- Sumerian cuneiform tablets recording contracts, governance documents, and business transactions. Interestingly, these "documents" memorialize agreements --- matters of consensus between two or more persons. These forms of external information storage are undoubtedly significant to early economic and political socialization. Human development of external information storage devices is unparalleled in the animal kingdom. From tablets, to papyrus, to paper, to the construction of libraries, to film and vinyl media, punch cards, optical and magnetic media, and semiconductors. But external information storage did not begin with out species. As Holldobler and Wilson documented in the case of the social insects: certain ants secrete pheromones in soil for colony ants to follow leaders from the nest to food sources and back. (See post of November 4, 2009). Soil becomes an information storage device. Urination by animals sometimes serves a social purpose to mark territory. Trees, plants, and soil become an information storage device. But this merely confirms my point about storytelling serving as an aid to memory. Sometimes that storytelling is an accurate, but memorable account of what really happened --- and we call that non-fiction. And other times it is exaggerated and manipulated to make it memorable --- and we call that fiction.
I want to close with two quotes that Gleick recites that say a little bit about what this book is about. From Claude Shannon: "The fundamental problem of communication is that of reproducing at one point either exactly or approximately a message selected at another point. Frequently the messages have meaning." As Gleick recounts, Shannon was not interested much in meaning, but just being able to determine that the information sent was exactly or approximately the same as the message received. And "approximately" was good enough for Shannon, because his mathematical algorithms would filter out the noise to provide a probability of what the information was that was sent. If this sounds like the quantum world that was described in Quantum (see previous post), well it is. And Heisenberg's uncertainty principle and Godel's incompleteness theorem figure into information theory.
Gleick also quotes Seth Lloyd, whose book Programming the Universe, inaugurated this blog two years ago: "The more energy, the faster the bits flip. Earth, air, fire, and water in the end are all made of energy, but the different forms they take are determined by information. To do anything requires energy. To specify what is done requires information." This is a statement about the physicality of information, a subject that I have alluded to many times over the past two years in various posts.
Much of The Information covers the history of the transmission of information from Sumerian times to the present. The media evolves from markings in the earth, to stone tablets, to paper wrapped in scrolls, to paper bound in book form, to rhythmic pulses of drums, to pulses of energy over electrical wire,to pulses of energy through the air. With Claude Shannon's revolutionary 1949 paper on a mathematical theory of communication, whose purpose was to address an engineering problem of "reproducing at one point either exactly or approximately a message selected at another point," the way we look at information transmission changed. As described in the August 23, 2009 post on Charles Seife's Decoding the Universe, Shannon understood that information could be measured and quantized, which would enable him to determine how much information could be transmitted through a given channel of transmission. Semantics and meaning are irrelevant to this exercise, but the measurements were extremely useful in solving various communications problems associated with telephone communications at the time and has likewise been useful in developing greater bandwidth so more information is capable of transmission at a given time from one point to another. Shannon also understood that information was physical and was subject to the laws of thermodynamics just as other physical features of the universe, and particularly the second law pertaining to entropy. (See August 17, 2009 post). Shannon further addressed the problem of "noise" in the communication channel that corrupted or interfered with information in transmission, and a mathematical means for filtering out that noise to determine probabilistically that the information received was the same as the information sent.
I have previously complained that whoever said that entropy refers to disorder did the world a disservice. (See August 17, 2009 post), and Gleick confirms that much confusion has ensued over the centuries in our discourse over the "second law" of thermodynamics because of the way entropy has been characterized. For those looking for some clarity about the principle of entropy, Gleick is worth reading. As initially conceived, entropy was a measure of the unavailability of energy for work because of dissipation. It referred to a "thermodynamic condition," where previously separate hot and cold bodies (could be a liquid or gas) generated steam that could be converted to energy for work, but once the hot and cold bodies mixed, the mixture achieved a uniform temperature and the amount of energy in steam dissipated making it unavailable for work. The "thermodynamic condition" that previously existed was said to have "dissipated," and there was no more energy available for work. The phrase "disorder" entered the picture because the previous thermodynamic condition where hot and cold bodies were separated and were capable of generating energy for work was considered "orderly," and the homogeneous mixture that was not capable of generating energy for work was considered "disorderly." The second law of thermodynamics stands for the proposition that the universe "tends" to flow from the orderly to the disorderly. Ironically, the "orderly" was viewed as a "less likely" macrostate, and the "disorderly" was viewed as a "more likely" macrostate. Probability theory therefore enters this discussion, and what is more probable is a homogeneous state where we are less likely to find separate distinct states.
Shannon's insight was that entropy was relevant to all dynamic systems, not just thermodynamics. To the physicist, entropy is a measurement of uncertainty about the state of a physical system. To the information theorist, entropy is a measure of uncertainty about a message, where it is less clear that the message that was transmitted is the same as the message that was received. Ironically, notes Gleick, humans, contrary to physical laws, seem bent on curbing entropy, making the environment in which they live, more orderly. We build things; we compile; we categorize; we separate. As Schrodinger noted, living things feed on negative entropy. The second law contemplates a closed system, and earth is not a closed system. Life feeds upon energy and negative entropy leaking into the earth's system. Similarly, humans have proven creative in dealing with probabilities and discerning information from communications that are not certain in order to make messages more certain and information theory provides us tools to do just that.
In contrast to Seth Lloyd and Charles Seife's works on the same subject, Gleick spends more time chronicling the technological development of information transmission. As I read on, I found myself thinking about a different subject to which Gleick gives only passing attention: memory. The subject of memory has been a continuous visitor to this blog, (See posts of September 9, 2010, September 28, 2010, November 27, 2010, and April 8, 2011). We tend to think of memory in terms of an information storage device. A 500 page book stores two million bits of information. A computer's hard drive or a CD-ROM store vastly more bits of information. These devices do not store words or images. They store information that encodes for words or images, but they also contain an electrical means for retrieving those images and words that are encoded. Thus a system of retrieving memory is essential to memory, otherwise it has no utility. This is entirely consistent with the description of the human brain's "architecture of memory" as described by Antonio Damasio. (See April 8, 2011 post). By Damasio's reckoning, the architecture of memory he describes evolved because of storage capacity limitations on our ability to retain images of prior events. Instead of files of memories of images and words, memory is found in the connections between cells in the brain. (See post of November 27, 2010). Shannon's research influenced the development of cognitive psychology, Gleick reports, because it became useful in understanding the limitations on our capacity to receive and store information, short-term and long-term memory, pattern recognition, attention, and problem solving.
Gleick does briefly allude to another subject that has received attention in prior posts: the human mind's capacity for storytelling and providing an explanation for what we experience, along the lines described by Michael Gazzaniga in Human. (See May 22, 2011 post and June 12 and June 28, 2011 posts). Storytelling has to be linked to memory formation and retrieval. Recording information, --- on sticks, on walls of caves, whatever --- says Gleick, "served as aids to memory." Homer's poetry, composed and sung in a mnemonic meter, "served first and foremost as an aid to memory." I think storytelling evolved in part to preserve our memory, but the irony is that those same stories can lead to distortions of the memory we try to preserve. Information is corrupted and does not copy accurately.
We have heard about this same sort of phenomenon in the context of the genome. (See November 27, 2010 post). The ultimate information storage device is the cell. The cell stores genetic material --- genes --- each of which is comprised of bits of information. At some point in evolutionary history, the means for communicating the information stored in the cell through replication became possible. Information contained in one information storage device was moved to another information storage device. Gleick quotes George Gamow: "The nucleus of a living cell is a storehouse of information," adding that it is a transmitter of information from which stems the continuity of life. Gamow described the study of genetics as the study of "the language of the cells." Matt Ridley (see November 27, 2010 post) would agree. When biologists discovered redundancy in the codons of the cell, they realized it was nature's way of dealing with "noise" in the transmission of information by providing tolerance for errors in transmission.
At some point in human evolution, external storage of information became important for survival. Gleick describes some of the earliest known examples of external information storage --- Sumerian cuneiform tablets recording contracts, governance documents, and business transactions. Interestingly, these "documents" memorialize agreements --- matters of consensus between two or more persons. These forms of external information storage are undoubtedly significant to early economic and political socialization. Human development of external information storage devices is unparalleled in the animal kingdom. From tablets, to papyrus, to paper, to the construction of libraries, to film and vinyl media, punch cards, optical and magnetic media, and semiconductors. But external information storage did not begin with out species. As Holldobler and Wilson documented in the case of the social insects: certain ants secrete pheromones in soil for colony ants to follow leaders from the nest to food sources and back. (See post of November 4, 2009). Soil becomes an information storage device. Urination by animals sometimes serves a social purpose to mark territory. Trees, plants, and soil become an information storage device. But this merely confirms my point about storytelling serving as an aid to memory. Sometimes that storytelling is an accurate, but memorable account of what really happened --- and we call that non-fiction. And other times it is exaggerated and manipulated to make it memorable --- and we call that fiction.
I want to close with two quotes that Gleick recites that say a little bit about what this book is about. From Claude Shannon: "The fundamental problem of communication is that of reproducing at one point either exactly or approximately a message selected at another point. Frequently the messages have meaning." As Gleick recounts, Shannon was not interested much in meaning, but just being able to determine that the information sent was exactly or approximately the same as the message received. And "approximately" was good enough for Shannon, because his mathematical algorithms would filter out the noise to provide a probability of what the information was that was sent. If this sounds like the quantum world that was described in Quantum (see previous post), well it is. And Heisenberg's uncertainty principle and Godel's incompleteness theorem figure into information theory.
Gleick also quotes Seth Lloyd, whose book Programming the Universe, inaugurated this blog two years ago: "The more energy, the faster the bits flip. Earth, air, fire, and water in the end are all made of energy, but the different forms they take are determined by information. To do anything requires energy. To specify what is done requires information." This is a statement about the physicality of information, a subject that I have alluded to many times over the past two years in various posts.
Subscribe to:
Posts (Atom)