Killing giants, myth busting and other valiant deeds (Books - The Oxford Book of Modern Science Writing & Reading in the Brain)

I just came across two excerpts in Richard Dawkins's collection of science writing that reminded me what gives me pleasure about reading science. One is geneticist J. B. S. Haldane's "On Being the Right Size" and the other, Zoologist Mark Ridley's "On Being the Right Sized Mates" from his 1983 book The Explanation of Organic Diversity. Haldane's essay muses on how the physical structure of animals evolved to the "right" size for their makeup. As an example he uses the giants from the books of his childhood,

These monsters were not only ten times as high as Christian, but ten times as wide and ten times as thick, so that their total weight was a thousand times his, or about eighty to ninety tons. Unfortunately the cross-sections of their bones were only a hundred times those of Christian, so that every square inch of giant bones had to support ten times the weight borne by a square inch of human bone. As the human thigh-bone breaks under about ten times the human weight, Pope and Pagan would have broken their thighs every times they took a step. This was doubtless why they were sitting down in the picture I remember. But it lessens one's respect for Christian and Jack the Giant Killer.

I love the fact that Haldane uses his childhood memory of Pilgrim's Progress to communicate to his reader what he is thinking about the physiological evolution of animal life. The best teaching occurs, I think, when the teacher themselves can get back to what initially ignited their own interest about their subject and communicate from that vantage point. Haldane then goes on a musing spree which covers the structure of members of the animal kingdom ranging from insects to giraffes. How an insect's structure allows it to fall without danger, but if it gets wet it is likely to drown. Tall animals require a certain strength pump and vessels for the circulatory system that convey blood to their extremities, however, this puts them at risk for high blood pressure or problems associated with vascular weakness. How do wings permit flight? How do different respiratory structures - those that have evolved with gills and those with lungs - accomplish the oxygenation of blood? And given these diverse means, what are the upper limits of the size of the animal that possesses them? Haldane not only informs us of the vagaries of the natural world we are a part of, he communicates the verve with which he observes that world, and with witty prose drives the reader forward. It is little wonder that he inspired Mark Ridley's observation that species have evolved to favor homogamy, that is, like mates with like. What I enjoyed about this brief essay is Ridley's debunking of the well-entrenched myth that in human affairs of the heart, opposites attract.

'it is a trite proverb that tall men marry little women...a man of genius marries a fool,' a habit which Murray explained as 'the effort of nature to preserve the typical medium of the race.' The same thought was expressed by the vast intellect of Jeeves, to explain the otherwise mysterious attractions of Bertie for all those female enthusiasts of Kant and Schopenhauer. The source of this proverbial belief is not certainly known; but one possibility can be ruled out. It did not originate in observation: humans mate homogamously (or perhaps randomly) for both stature and intelligence.

Myth-busting is not just a darn good time - especially when indulged in with such gusto - but doubting our assumptions is vital to the continued development of our knowledge. This is also another of many instances in Dawkins's juicy compendium in which learning something new is married to lucid, entertaining writing. The danger of this volume, however, is its tendency to bloat the TBR list. I've made it a rule to only jot down my desired titles at this point, and not engage in any impulse buying. We'll see how long that holds! Here are my other posts related to The Oxford Book of Modern Science Writing 1, 2.

I have also begun Stanislas Dehaene's recent book Reading in the Brain and, speaking of gills, it is packed to them with information about how the brain accomplishes the act you are performing right now - reading. An accessible and engagingly written volume. I tore through the first 60 pages. More on that soon.

Mind and brain - partners in movement (Books - i of the vortex by Rodolfo Llinas)

Rodolfo Llinas's 2001 book, i of the vortex attempts to bridge our knowledge about the concepts of mind and self and our knowledge about brain cells. Somehow when our brain receives sensory stimuli from some source in the world (say a little red car driving down the street) - light acts upon the retina, waves of compressed air act upon the ear's basilar membrane - if that information is to be used, its gets recreated as an image represented in the language of the brain. If we aspire to own such a car, our interest will perceive the its meaning as the object we are saving to buy. If we are in the middle of the street and the car is driving towards us at 80 miles per hour, we will perceive its meaning as a heavy piece of metal with potential to do us harm and a good reason to move our legs and get out of the way. The pieces of information are reassembled in such a way that they are relevant to given states. An image is made of 'car' in one context or another and yet, if we opened the brain and looked at the tissue that made that image, we would see nothing that looks like a car. The car doesn't drive onto ones retina, and resemble a car as it makes its journey from our eye to our thalamus to our cortex. What goes in does not come out, but is an image translated into the language of electrical changes spoken by our neurons and generated according to a context that gives the image potential use. Mind, according to Llinas, is the present internal state that determines the creation of that image relative to its use given that state. Relative to predictions it makes about the events occurring around us, the brain plans movement, executing the command to carry out such movement if it is necessary.

The central generation of movement and the generation of mindness are deeply related; they are in fact different parts of the same process. In my view, from its very evolutionary inception mindness is the internalization of movement.

However, different states are concurrently overlapping and vying for primacy in each of us at any one moment. In the example above, our red car could be not only our heart's desire but also a potentially lethal projectile at the same time. Yet, if our brain is to make its predictions useful, there must be some arbiter of these concurrent states.

Self is the centralization of prediction.

Llinas then relates how potential movement may have determined the evolution of the brain as its looks today and how the brain's cells carry out the twin functions of creation of states and prediction of future needs, given what we know about their properties. Which has taken me to the half-way point.

Llinas's writing is cogent and quickly paced. This book is really philosophy married with neuroscience and Llinas is skilled at describing abstract concepts, attaching them to the structural and electrical facts of neurons, without losing either thread. Some ability to walk around in the language of contemporary neuroscience is necessary to get through the chapter on neurons. It is written at a graduate text book level, but having only one chapter to spend on these intricacies he writes an effective summary. I don't know if that will make it easier for the first-time reader or more difficult. I will know better when I reach the end of his argument if one could skim this chapter and still get the gist of the integration Llinas is trying to build between brain and mind. His is a grandiose plan - the flip side of Buzsaki's more narrowly focused and longer work on the brain's oscillatory properties. Llinas seems to want to devise the integrated theory of absolutely everything - mind, brain, self, consciousness - we have all the information we need, the premise seems to say, all that's left is for me to tie it all together. I'm glad to report that so far, he builds his story methodically and makes his connections modestly.

Silver Lining?

Jonah Lehrer has an excellent article in today's New York Times Magazine about a new way that a psychiatrist and an evolutionary psychologist, Paul Andrews and Andy Thomson, are thinking about depression, or at least one of its features - rumination. If it such a widespread condition, they ask, then is it possible that it is somehow adaptative? Don't worry, both the article and the scientists are not belittling the pain of being depressed.

Lehrer explores their idea that rumination, which is typical to the grief reaction, is more than simply pessimism, it is also the kind of extended expenditure of mental energy on a problem out of which can be born new understanding. The ruminative feature resembles a part of the cognitive process that often results in successful creations. I would add my thought that, in a situation of pain or loss, the lack of interest in activity, food, or sex, keeps one physically passive at a time when the prediction-making part of us does not have the optimal setting for activities requiring good coordination and fast reaction-time, and we may therefore make bad judgments. So instead our body demands that we sit, collect, and turn things over. This could also be another adaptive feature of the mechanism. Lehrer also gives space in his article to discuss the criticisms many psychiatrists have of this new notion.

I would have appreciated brief inclusion of the current theories of what is happening not just in the psyche, but in the brain, during depression. One theory receiving a lot of attention is that of reduced neurogenesis (less creation of new neurons) in certain parts of the brain. I wonder how this correlates with or contradicts Andrews and Thomsons hypothesis? Their idea began with the prevalence of depression, which Lehrer describes as 7 percent. Is that a world-wide statistic? A Western society statistic? An American statistic?

I have often heard the construct of depression critiqued as an illness of wealthy privileged societies. That made me think two things: a) adaptation occurs by random mutation (although it's the Natural Selection part that people most like to focus on) and, b) the notion of which features are adaptive for humans needn't be monolithic. Humans haven't all evolved to one perfect homogeneous species and stopped. We are evolving many different features. Some of us are hairy, some smooth. We have different pigments shading our skin, which were adaptations to different environments. We have different length femurs, so why not different cognitive styles? Most of us are no longer hunters and gatherers. Perhaps we are becoming aware of a random mutation that gives us a different default setting for our prediction-making organs (our brains) to favor periods of less action, less reproducing, and more rumination. Perhaps in certain contexts in which humans live this will make us more adaptive and therefore it will survive over the long run. Perhaps the features of it that are maladaptive in other contexts will result in it disappearing over millenia. We won't be around to find out. But I am glad for Lehrer's thoughtful look at scientists who are trying to look at a cultural and scientific phenomenon with a longer view. I always admire his writing and, as usual, this piece gives us insight into novel thoughts about topical issues of mind and psyche. It also rekindled in me some thoughts about our society's knee-jerk propensity to always value happiness above grief, anger, passion, or doubt. We have a range of affective states. Perhaps each part of that range has its uses.

The music of our brain (Film - The Music Instinct & Book - Rhythms of the Brain by Gyorgy Buzsaki)

Typically, the new year is rung in here with friends and fondue but The Ragazzo has been so sick that he was in bed and I celebrated by doing the laundry, watching a video, and going to bed at 10:30. Woo- hoo. Hope you brought in 2010 with more appropriate pomp.

The Music Instinct: Science and Song is the video I watched. It is a film by Elena Mannes first aired on PBS. I received it from The Ragazzo's brother and sister-in-law this christmas and it is about the latest research on music and neuroscience - one of my pet topics. It features all the usual PBS-type folks - musicians Bobby McFerrin and Yo-yo Ma, Oliver Sacks, and physicist Brian Greene - but it had pretty decent coverage of the major researchers in the relatively small field of music and cognition. It begins with a discussion between scientist Daniel Levitin and musician Bobby McFerrin asking - "Why music?" Levitin was the most well known researcher in the film because of his book This is Your Brain on Music, but they also had John Sloboda, Robert Zatorre, Isabelle Peretz, Sandra Trehub, and Aniruddh Patel (among others) - all respected researchers in the field. It was better than some pop-science I've seen in presenting more than one side of an argument, but it did not offer a narrative that clearly told the inexperienced viewer that that is what it was doing. It wanted, like most television fare, to make grand claims that could not be supported by the research presented. They ended with the Audra McDonald's voice-over saying - "Why music? It is written into our very being. Science is showing us that song is at the core of life." The film is straining to tell us that music is tied in some essential way to our DNA, although in actuality the film ended with a few differing opinions about why humans make music and it would have been more honest to have told that story. However it makes for an engaging primer on the subject for the lay-person and I found the inclusion of Brian Greene useful in that the program discussed not just the esoteric musings of a small group of specialized researchers about why music might have evolved in human culture whether as an adaptive feature or as a useless adornment, Greene discussed music as a physical phenomenon - a patterned disturbance of air - or a wave - and Levitin stressed music's ability to coordinate the firing of neurons and that reminded me of a book I have been meaning to pick up for the last six months - Rhythms of the Brain by Gyorgy Buzsaki - so I unearthed it and began reading last night (we really know how to party here at Bookeywookey central).

Buzsaki book does not address music per se, it focuses on rhythm, particular oscillatory patterns or periodic disturbances to a system or state as they occur across time. This phenomenon is found throughout nature and Buzsaki is particularly interested in groups of neurons that fire in patterns, establishing a temporal metric which could then organize larger patterns of activity among cells in the brain. This is seen as a self-organizing action that subsequently impacts the brain's cognitive and motor functions and whose temporal nature is essential to what may be the brain's primary reason for existing - predicting what will occur next in the environment.

Predictions and relationships are constructed by ordering the succession of events according to elapsed subjective time. We are usually able to say which of two events happened before the other...the cause precedes the effect in time.

If one observes how reactive systems evolved from single-cell creatures to nerve nets in hydra to complex mammalian brains over millenia, the substantial adaptation offered by a brain like ours is that of predicting events before they occur and the ability to more sophisticatedly collect data from our environment and use it to intercede in what would otherwise be an automatic repertoire of responses.

Buzsaki's range of knoweldge is broad - bringing in chaos theory, electrophysiology, mathematics and biology. His language is the language of science - when he day dreams he tells you so and when the information he presents has been measured via experimental means and expressed as a probability (as all study conclusions are) he tells you that. His writing is down-to-earth and very engaging and since he writes about the phenomenon of rhythm, I find his thinking stimulating for relating one of the features of music (which evolved along with the rest of the natural cultural word) with brain function. A superb book so far.

Buzsaki and my continued exploration of the superb Irish novelist Deirdre Madden with her The Birds of the Innocent Wood make up my reading as 2010 begins. And yourself?

It's all about protein

It's not the number of neurons that increase the computing power of a particular species' brain, and hence the potential complexity of its behavior. Rather it is the structure of the synapses - the microscopic spaces between neurons - how many proteins are present there, and how many different types of structures those proteins combine to construct, according to Dr. Seth Grant and his colleagues. Their recent article in Nature Neuroscience is summarized in Nicholas Wade's article in today's Science Times.


This study is particularly interesting for its comparison of synaptical structure across different species. I find the structure of the neuron a fascinating subject because our behavioral complexity - the difference between humans being able to speak and reflect on their own thoughts versus a slug's simpler cognitive capacities - is the difference between the number of proteins present in their nerve cells, and that influences, as this article puts it, our processing power. Here's why: Our billions of neurons are like strands of microscopic wire strung end-to-end throughout our nervous systems. They communicate with each other both chemically and electrically and if the message is strong enough, those communications result in a behavior - a hand moves, the heart beats, anger is registered on another's face and we run, etc.... Proteins are the building blocks for the various chemicals that neuron's pass between each other to facilitate or hinder the activity of the succeeding neuron. They also help package those chemicals for distribution, they create mechanical devices which propel those packages through pores in the synapse, others which pick up excess chemicals and return them to the cell. Still other proteins are embedded along the membrane of each neuron that allow passage of different charged particles in and out of the cell, which permits the 'firing' of nerve cells that you have probably heard people talk about. All electrical activity, whether it fires up your lamp at home or your neurons, is a result of differences in charge. (Think of how putting the positive ends of two magnets together creates a force that you can actually feel) Simpler species have only evolved systems that use one or two types of charged particles to flow - say, potassium and sodium. Whereas more complex species have additional types - they (we) allow potassium, sodium, calcium and chloride - those channels also have evolved subtypes each of which has a somewhat different mechanical structure and hence a different action. Each of those differences adds a new way one cell can 'fire' or talk to another nerve or muscle cell. Some cells give one big burst of electricity, others give groups of bursts in rhythmic patterns. Some cells produce messages which function only to change the message of another cell. It is the summed action of millions of these cells which ultimately determines whether a behavior happens or not. Does our hand raises and grasp our cup of coffee without looking while continuing to type a blog entry with one hand? Or does it knock it off the desk instead?

The advantage of a complex animal's computing power is like the difference between having an alphabet with three letters and one with 26. With three letters one has a modest number of combinations one can produce: ABC, ACB, AAB, BBA, etc... Those three letters do give us a decent number of combinations and you could think of each of those combinations as a 'message' output by the cell. But then think of our 26-letter alphabet and consider the number of words in our dictionary. An increase of 23 letters (a small number of building blocks) buys us millions of possibilities in terms of how we can combine them. A sea slug with only a few varieties of potassium channels only has a few possible ways its nerves can fire - hence the limited repertoire of behaviors one might expect from the slug. They can move their gill to get oxygen, they can wiggle their tail for movement and avoid danger, they desire nutrition and pursue it, but we don't expect them to suddenly learn to fox trot no matter how much training we might provide. The human brain is capable of a startling number of actions and subtle variations on those actions (it also has an impressive number of ways it can mess up as well). That is because of the inherent combinatorial possibilities afforded us by the way our 1000 neural proteins have evolved to combine. It ain't a perfect machine by a long shot, we have also evolved violence, neuroticism, and schizophrenia, but it is pretty remarkable system nonetheless. Our ability to cook, write poems, and reflect on our carbon footprint have evolved because we have more ways our cells can 'fire.'

Hopefully that added to your understanding of this article and didn't just confuse you. Feel free to ask questions if this subject interests you.

The roots of communication are the roots of esthetics

Natalie Angier muses today in the Science Times about art - from whence it came and why. Is it the product of oversized brains that have too little to do? Some theorists have deemed art a way of preening. Having worked in the field for twenty-odd years, I can certainly see the connection. It starts with putting pictures up on the refrigerator and tales of great divas let us know where it can end up. Others see art as a social glue - like religion. Ellen Dissanayake, a scholar of evolution and art, believes that, given the amount of time and resources art consumer, it must be an evolutionary adaptation. Unfortunately this article skims along the surface of the subject without really getting into it. Does that mean if one person makes art then it uses a lot of their time or does that mean that it uses a lot of an entire society's time? Is that statement supportable? By resources does she mean material resources or cognitive ones? She also asserts :

Art also gives us pleasure...and activities that feel good tend to be those that evolution deems too important to leave to chance.

Stated this way, it seems spurious to me. Ice cream gives us pleasure, we are not evolutionarily adapted to it. We are adapted to consume calories where we can get them, a by-product supposedly left over from when we were roaming the earth more dependent on the whims of nature than on Safeway. This would point more to art being a by-product of our evolutionary attraction to bold colors and sounds, or to pattern recognition. Additionally, art is not necessarily just pleasurable - it is sometimes more deeply involving, intellectually stimulating, a complex synthesis, a way to represent things that are meaningful to us, a way to commemorate death, a way to leave a mark. However it may be all these things because it is the essence of what is engaging and attractive to us and that is exactly why Ms. Dissanayake has begun studying the communing rituals between mother and infant for signs that they might evolve to become the building blocks of choreography or music. It's an interesting notion that Ms. Dissanayake's book Art and Intimacy: How the Arts Began no doubt gets into it in more detail. It is interesting to ponder that we might be hardwired to be engaged and attracted by themes and variations on sound and movement and that that is the origin of our finding a textile design or a church spire esthetically pleasing.

Smart is the new Sexy! (The evolution of behavior and the brain)

Blatant benevolence and conspicuous consumption

From The Economist

Hat tip: 3 Quarks Daily

GEOFFREY MILLER is a man with a theory that, if true, will change the way people think about themselves. His idea is that the human brain is the anthropoid equivalent of the peacock's tail. In other words, it is an organ designed to attract the opposite sex. Of course, brains have many other functions, and the human brain shares those with the brains of other animals. But Dr Miller, who works at the University of New Mexico, thinks that mental processes which are uniquely human, such as language and the ability to make complicated artefacts, evolved originally for sexual display.

Geeks everywhere will be vindicated. Smart is the new sexy...or the old sexy, I guess you would have to say. You can read the complete article in The Economist. Miller and his collaborator, Vladas Griskevicius recent published their theory in the Journal of Personality and Social Psychology and the article is careful to point out (thank you for responsible science reporting) that testing it will take all long time. They have begun by examining two traits - conspicuous consumption and altruism toward strangers. The second, the article claims, has "no obvious payoff" for humans.

I find the construction of hypotheses about human behavior fascinating. The best inquiry, I have been taught by one of my teachers, looks at a problem on multiple levels. For example, if you are examining a question about cognition - say, problem solving - your idea should have support on the anatomical level (one level lower, if you will) and should be applicable to how we take tests (one level higher). Cognitive neuroscience is by its nature multi-disciplinary. Questions about language and behavior often have one foot in evolution in that inquiring minds want to know what every 4-year-old scientist asks multiple times a day - "Why!" I have read more than once recently that altruism toward strangers has no payoff, and I'm confused by it. Given the fact that we have evolved as social creatures, wouldn't acts for the good of society be valuable to the preservation of the species - or does our own personal strand of DNA always take precedence? I guess I should really take a course in evolution and genetics and find out. I enjoy hypotheses about behavior because this question of 'why' necessarily combines imagination with science.

Leewenhoek grinding a lens that provided powerful enough magnification to see microbes changed what we knew about the world concretely. The existence of microbes is confirmable. But what motivated the evolution of our brain - can we ever comfortably conclude that - yes indeed, our brain DID evolve for the purpose of wooing our mates. What a relief to know! In a discussion involving natural selection, were talking about understanding which characteristics were advantageous to survival given the environment millions of years ago. This inquiry must necessarily combine some parts imagination with some parts science. Good research does involve imagination, I believe, and its product is useful to us in how we understand ourselves if it can produce a compelling narrative.