Saturday, November 27, 2010

Matt Ridley, Genome (1999)

A television show, Law and Order, opens each episode with a narrative line about the role of the police and prosecutors in the criminal justice system, which closes, "And these are their stories." Matt Ridley might have opened Genome by stating, "There are 23 chromosomes that make up the human genome, and each have special roles (plural) in determining or influencing our development, our physical attributes, our behavior, the kind of diseases we suffer or have immunity from, how long we might live, and when we might die. And these are their stories." Don't misunderstand me. Genome is not a complete encyclopedia of either genomics or the human genome. Just 23 interesting stories from one of the world's fine science writers, each story artfully tied to one of the 23 human chromosomes, from largest to smallest, covering topics such as life, species, history, fate, environment, intelligence, instinct, self-interest, sex, disease, stress, personality, development, life and death, memory, gene therapy, politics and ethics, eugenics, free will and determinism. The breadth of the subject-matter covered by this volume speaks to almost all of the topics covered by the books previously described in this blog, including a central theme: that units of information are the most fundamental units of life. (See September 28, 2010 post).

Ridley calls the genome a book, the chromosome a chapter, the gene a story, an exon a paragraph, a codon a word consisting of three letters, and a base is a letter, either (in the case of DNA) an A, C, G, or T (or U in the case of RNA), for adenine, cytosine, guanine, and thymine, each consisting of one or two aromatic rings and arrangements of carbon, hydrogen, nitrogen, and/or oxygen atoms. These chemical units are the basic units of information that comprise life forms, but alone they do not give rise to life. What gives rise to life is (1) the pairing of these letters along a double helix that makes up DNA, and (2) their subsequent transcription into RNA to form three letter codons, which, (3) are subsequently "translated" into a specific amino acid depending on which three of the four letters are transcribed and their sequence. (4) The particular chain of amino acids creates a protein. By this process, it is said that "genes" code for "proteins." While the RNA amino acid chains may have been the earliest form of life, "life" as we know it received a boost with the creation of cellular membranes to form the first cells that carried the proteins containing genetic information central for the cell's organization. This development is still not fully understood.

This ability of the genes to copy themselves, read and transmit their story, under the right conditions, is the ability to create another life form. My son once asked asked me, "What is Life?" a question posed in his high school biology class, and I replied that at its most fundamental level it is carbon-based, with a mechanism to replicate itself. The only two things I would add, consistent with the very first book discussed in this blog, Seth Lloyd's Programming the Universe (see August 17, 2009 post) is the ability of these units of information to communicate among themselves --- an electrochemical means --- to say "Let's stick together," or "Let's avoid each other," and then to store itself as if in memory. This is what we find in the genome, whatever the species.

This story never ceases to amaze me. Life began with RNA --- which by itself can replicate itself, and translate and transmit its meaning, as well as catalyze with --- break up or join with --- other chemicals, creating amino acids and proteins. The storage device for these words and paragraphs is DNA. An RNA gene found on chromosome 1 translates the information found in DNA to proteins, which become the primary agent for carrying out the direction specified by the information contained in the genes within a cell.

I cannot cover every "chapter" in Genome, but four topics that reappear throughout this blog --- so we can connect the dots --- are important in my mind: (1) is behavior found in our genes? (2) the role of our genes in our development after birth, (3) human memory and the mind; and (4) determinism vs. free will.

Is behavior found in our genes? This topic was first confronted in the post on Richard Powers' novel Generosity (November 30, 2009 post), Frans DeWaal's The Ape and The Sushi Master (June 17, 2010 post), and subsequently Oren Harman's The Price of Altruism (October 13, 2010 post). The answer then, as it is now, is no. There is no gene for spitting or laughing or speaking English or for believing in a god. What genes do code for enables or influences behavior, but they do not determine specific behavior. Just as it would be incorrect to say that behavior is entirely written in our genes, it would also be incorrect to state that behavior is entirely attributable to environment, including the nurturing, learning, social and cultural environments. Behavior is the outcome of the genome that defines us and the environment in which we develop and live.

Ridley notes the significance of instinct, something which was important to Darwin in The Origin of Species. Behavior that is instinctive to a species is arguably heavily enabled or influenced by genetic information. So we may refer to a language instinct, to borrow Steven Pinker's words, but a language instinct does not develop without some environmental influence. The genes that become proteins instruct the creation of the mouth, the tongue, and the air passages that enable human speech, and further instruct in the creation of the modules of the brain and the neuronal pathways between them that enable human speech and perhaps even language syntax. But at some point in the course of a life, learning takes over. The ability to learn --- social behavior --- is also something that is enabled or influenced by genetic information, but genes are not the end of the story.

The role of genes in development. This story was detailed in Sean Carroll's book Endless Forms Most Beautiful, which accounted for the role of the Hox and hedgehog genes in providing a program for both embyonic development and development after birth. These genes regulate cell division, the timing at which genes are switched on to control development, and determine such things as symmetry in the body of an animal, where arms, legs, antennae, fins, fingers and the like appear. Ridley retells this story on Chromosome 12. This is one of the most fascinating stories in evolutionary genetics as these are among the oldest of genes.

Memory. One of the more important subjects in the study of the brain is its plasticity, the brain's ability to change by removing, adding or strengthening neural connections. "When you learn something," Ridley notes, "you alter the physical network of your brain so as to create new, tight connections where there were none or weaker ones before." Connections between never cells "not only provide the mechanism of memory, but are memory." Ridley is not clear on how specific genes are tied to learning and memory, but he suggests that proteins connected with certain genes "are probably needed for holding the synapse closely together." We know more about the process by which memories are created and stored in the brain: sensory information is received in the perirhinal cortex found in the medial temporal lobe and sent to the hippocampus and to the diencephalon for temporary storage. If the information is significant enough for more permanent storage, it is sent back to the neo-cortex as long-term memory. Eric Kandel's research, documented in his memoir, In Search of Memory, traces the electro-chemical process in the brain by which connections between the neuronal connections at the synapses of neurons are strengthened.

Learning "is the opposite of instinct," Ridley says. "Instinct is genetically-determined behavior; learning is behavior modified by experience. . . .Human beings achieve by instinct the same things that animals do. We crawl, stand, walk, cry and blink in just as instinctive a way as a chick. We employ learning only for the extra things we have grafted on to the animal instincts: things like reading, driving, banking and shopping." Consciousness, Ridley quotes another, "is to enable [the child] to learn things which natural heredity fails to transmit." The brain is created by genes that designed the brain to be modified by experience.

Determinism vs free-will. The final chapter is almost whimsical --not truly a story about Chromosome 23, but an excuse to pontificate on whether free-will is possible given that a combination of genetics and the environment seems to determine everything about us. Free-will, in my view, if it exists, is enabled by the brain --- it is tied to the same type of issues that Ridley discusses in connection with learning and memory. Human behavior, says Ridley, is unpredictable in the short-term, but quite predictable in the long-term. As an example, he cites that at any given time during a day one can choose to eat or not to eat, but over the course of a day one will have to eat. When one eats is a function of genetic and external influences that makes behavior unpredictable, but not undetermined. "Freedom lies in expressing your own determinism:" being able to control voluntary movement in the gap between short-term when behavior is unpredictable and the long-term when it is predictably determined, It is in the brain of humans, and perhaps some other animals, that the ability to control voluntarily movement is found. And genes have enabled this ability in the design of the brain.

Saturday, November 13, 2010

Miriam Boleyn-Fitzgerald, Pictures of the Mind (2010)

Until the 1990s, much of what we knew about specific parts of the brain came from clinical observations occurring in the course of evaluating patients who had suffered brain lesions or other trauma. The neurologist knew that a certain part of the patient's brain had been damaged and knew that the patient's behavior was altered in some way. From these observations, the expert could conclude that the damaged part of the brain had some role in the emotional and/or cognitive life of the patient and generalize. Autopsies could, in some cases, lead to similar kinds of findings. But there are ethical limitations on intruding too deeply into the brain of a living patient unless it is essential to the patient's welfare. Michael Gazzaniga discusses these limitations in his book Human (September 27, 2009 post).

Imaging technology --- particularly functional magnetic resonance imaging (fMRI) and positron emission tomography (PET) --- has changed that, and Miriam Boleyn-Fitzgerald introduces that technology to explore how much we have learned about the brain, memory, our humanness and sense of self, and psychiatric therapy in just the past 20 years. She also explores the role of imaging technology and brain scans in the courtroom, as criminal defendants seek to excuse their antisocial behavior and explain that excuse to a jury.

Boleyn-Fitzgerald's book is not a bad follow-on to De Waal's Age of Empathy (see previous post), as imaging technology has been useful to see the brain's reaction to perceptions of others in pain. But there is almost a new-age component to this book, a suggestion that imaging technology will confirm that Eastern contemplative traditions --- in contrast to Judaeo Christian religious traditions --- are more closely linked to our mental welfare. Confirming what DeWaal noted, Boleyn-Fitzgerald reports "the insula --- a part of the limbic system that serves as the key interface between physical sensations and emotions --- and in the temporal parietal junction, which appears to play an important role in processing and understanding the emotional states of others" are associated with compassion and empathy. The fMRI research also shows that these areas of the brain are also very active when Buddhist monks meditate, and, when combined with knowledge of the brain's plasticity, these associations suggests that the brain may be trainable (particularly in younger ages) through meditative therapy to learn to become more empathetic and less self-centered. That is the primary message that Boleyn-Fitzgerald delivers here --- what we learn from scanning the brain will inform us better about methods or strategies to promote mental and social health.

Medical imaging technology has played a role in identifying the parts of the brain that control our decision-making and the formation of judgments. Consistent with Gazzaniga's research as reported in Human, as well as the research of Antonio Damassio and Marc Hauser, there is a predispostion founded in feelings and emotional responses --- not utilitarian calculation --- for the mind to solve moral dilemmas in a manner that is not inconsistent with the moral rules societies tend to live by. Imaging studies support this research.

"One property of human consciousness," Boleyn-Fitzgerald writes, "emerging from the scanners --- one fact that now seems inarguable --- is that the neural activity associated with the subjective experience of self cannot be located in a single area of the brain. This finding matches what we now know about the entanglement of neural circuits associated with emotion, cognition, memory, and moral decision-making." Our brain is decentralized, and there are separate parts of the brain that the scanners show are activated when "I" is acting and feeling in the present and "me" is trying to explain and understand what is happening. Gazzaniga explained this in terms of one part of the brain telling a story about ourselves, and the other part of the brain tries to interpret our story. Knowing this, Boleyn-Fitzgerald believes, will better enable us to know our "self" and our "identity," and assist in our ability to regulate our self.

Tuesday, November 9, 2010

Frans DeWaal, The Age of Empathy (2009)

Good book. Poorly chosen title. Whether DeWaal chose the title The Age of Empathy or the publisher thrust it upon him, it was clearly inspired by the euphoria following the November 2008 election of Barack Obama as President of the United States as though the election launched a new era of human behavior. He shares a similar hope with Jose Saramago's hope for a kinder, social society as expressed in The Notebook (September 28, 2010 post). Now, two years later, on the heels of the midterm elections in the United States, empathy is hardly a name that I would assign to these times.

Nor does the title align well with one of De Waal's essential points about human duality, which is illustrated in the following passage:

"Humans are bipolar apes. We have something of the gentle, sexy bonobo, which we may like to emulate, but not too much; otherwise the world might turn into one giant hippie fest of flower power and free love. Happy we might be, but productive perhaps not. And our species also has something of the brutal, domineering chimpanzee, a side we may wish to suppress, but not completely, because how else would we conquer new frontiers and defend our borders? One could argue that there would be no problem if all of humanity turned peaceful at the same time, but no population is stable unless it's immune to invasions by mutants."

Even De Waal admits that empathy --- the ability to identify with and feel a connectedness to another --- is as much a part of us (and other species) as selfishness, violence, and egocentrism. "I rate humans among the most aggressive primates," he writes, "but also believe that we're masters at connecting and that social ties constrain competition. In other words, we are by no means obligatorily aggressive. It's all a matter of balance: Pure, unconditional trust and cooperation are naive and detrimental, whereas unconditional greed can only lead to the sort of dog-eat-dog that Skilling advocated at Enron until it collapsed under its own weight." So contrary to the opening line of the book, "Greed is out, empathy is in," there will never be an "age" dominated by empathy or any other single other characteristic of our personality.

Our capacity for cooperation, altruism, and other social instincts is certainly biological, and it is a product of evolution. We have much to learn about what makes us human from learning about the behavior of other species from which humans evolved as we do from observing our own behavior. This is De Waal's primary thesis. And this thesis is no stranger to this blog and previous posts, including De Waal's own The Ape and the Sushi Master (June 17, 2010 post), Oren Harman's The Price of Altruism (October 13, 2010 post), Dacher Keltner's Born to Be Good (July 16, 2010 post), Holldobler and Wilson's The Superorganism (November 4, 2009 post), Michael Gazzaniga's Human (September 27, 2009), Marco Iacobonni's Mirroring People (September 18, 2009 post), and Christine Kennealy's The First Word (August 31, 2009 post).

De Waal takes aim at three myths: (1) the myth that our ancestors --- 4 foot bipedal apes --- ruled the savanna in Africa; (2) that human society is a voluntary creation of autonomous men; and (3) that our species has been waging war for as long as it has been around. Our ancestors were likely both prey and predator and survival favored genes that encouraged collaboration and companionship. The idea that humans were autonomous falsely presumes they had no need for anybody else and could voluntarily choose to live apart, uncommitted to anyone else or any place. A warlike initial state of nature that philosophers like Rousseau imagined that was overcome by social compacts is actually the reverse of human evolution: war on a grand scale, like we have known for centuries, came only after social hierarchies were formed and wealth was created. The early human species was probably defined more by social commitments and small scale collaboration that promoted primitive economic exchange and division of labor.

At the biological core of our humanness is the limbic system, which, from an evolutionary perspective, is one of the oldest parts of our neural network in the human brain. It is a part of the brains of other species as well. Antonio Damassio identifies the limbic system as a critical regulator of feelings and emotions in The Feeling of What Happens, and it is central to understanding human consciousness. De Waal says the limbic system allows emotions such as affection and pleasure, and paved the way for family life, friendships, and other caring relationships. Other parts of our neural network allow us to store memories of these feelings and emotions and allow us to recall the context in which we previously experienced them and then to "understand" them. A key line here is De Waal's statement, "Bodily connections come first --- understanding follows." Mirror neurons, as described in Iacobonni's Mirroring People (September 18, 2009 post), are active in these other parts of the neural network known as the brain that allow us to "read" the minds of others, enabling us to connect with others, and facilitate the the experience we call empathy. "De Waal calls this emotional contagion: seeing another's emotions arouses our own emotions, and then we build "a more advanced understanding of another's situation." Later, he adds, "Empathy engages brain areas that are more than a hundred million years old. The capacity arose long ago with motor mimicry and emotional contagion, after which evolution added layer after layer, until our ancestors not only felt what others felt, but understood what others might want or need."

True to his dualism, just as De Waal recognizes that emotional contagion probably starts immediately with the mother-child relationship and that early communication fosters a bond, a second phase begins just months later in the course of child development when the child begins to develop a sense of self. And empathy, De Waal believes, "requires both mental mirroring and mental separation." The former occurs when we see another person in a particular emotional state. The latter occurs when we parse our own emotional state from the other, and this allows us to "pinpoint the actual source of our own feelings." De Waal attributes our dualism to the existence of VEN cells in the brain --- Von Economo neurons --- that differ from other neurons and are unique to humans and their recent ancestors. Physically, VEN cells are long and spindle-like and reach deeper into the brain. Research shows that when parts of the human brain that contain these cells are damaged, behavior is marked by a loss of perspective-taking, empathy, embarrassment, and future orientation. Besides humans and certain apes, these cells are also found in dolphins, whales, and elephants, where behavioral research shows they have the capacity for empathy that is not found in other species.

De Waal frets that the reluctance of some segments of human society to talk about animal emotions has "less to do with science than religion." Eastern religions, which tend to embrace the connectedness between humans and other species, don't show this reluctance, but the Judaeo-Christian-Muslim religions tend to place humans on a pedestal as the only intelligent life on earth and show greater reluctance to connect themselves to other species as opposed to abstract spirits that purportedly have equal or greater intelligence. De Waal believes this is because of their origin in an existence where humans were desert nomads --- where other animal life was sparse compared to other geographic regions on earth.

From our capacity for empathy evolves reciprocal behavior and ultimately altruistic social rules. But given the dualism that reflects both our empathetic self and our self-centered self, we also have competitive behavior and ultimately social rules to regulate that competition. This leads De Waal to identify two types of fairness principles that are at the core of these social rules: fairness that seeks a level playing field (equality) and fairness that links rewards to effort, and both are "essential," De Waal says.

My observation is that the pendulum swings between the two types of fairness --- one which is grounded in empathy and the other which is grounded in the sense of self. One type of fairness does not displace the other entirely. So if this was the Age of Empathy, the Age of Greed and Discord is merely sublimated for a period of time. But De Waal appears to be the optimist in contrast to Jose Saramago, the pessimist, on this point, whom I quoted in The Notebook (September 28, 2010 post), concluding, "It is most likely, however, that there is no remedy for any of the above and that civilizations will continue to collide, one against the other."