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The Delusions of Certainty

Page 5

by Siri Hustvedt


  In popular culture, the word can be made to mean more and less or less and more, as in Hardwiring Happiness: The Practical Science of Reshaping Your Brain—and Your Life (2013) by Rick Hanson, a neuropsychologist. This self-help manual “grounded in neuroscience” is described as “a simple method that uses the hidden power of everyday experiences to build new neural structures full of happiness, love, confidence, and peace.”46 Here “hardwiring” appears to be standing in for neural plasticity itself, the dynamic character of synaptic connections in the brain, which connotes flexibility, not rigidity. (How neural structures can be “full of” abstract qualities such as “love” is a profound question that goes unexplained.) At the same time, the word “hardwiring” is used to suggest that with a few simple techniques, you can rewire yourself permanently into a hardwired state of uninterrupted euphoria. You begin with flexible wires and end up with hard, happy ones. The proverbial cake is had and eaten, too. The unarticulated assumption here is that by thinking good thoughts, you can change your brain and make yourself happy. As in CBT, conscious thoughts affect physiology, in this case brain wiring. Thoughts are somehow connected to the brain but are also somehow beyond it. Can what we think of as mind shape what we think of as brain? Is a mind different and separate from a brain? The problem of dualism and monism, one substance or two, is implied but not explained in this pop version of the hardwired brain.

  In his book Hardwired Behavior: What Neuroscience Reveals About Morality (2005), the psychiatrist Laurence Tancredi employs “hardwired” in yet another way: “If moral rules weren’t a product of social ideas handed down through generations,” he writes, “would we be in a state of anarchy? Not likely, because the underlying foundation for morality appears more and more to be in our biology, hardwired in the brain.”47 Notice first that the phrase “hardwired in the brain” modifies the word “biology.” The two are treated as synonymous. “Hardwired” appears to be less metaphorical than literal because Tancredi immediately launches into a much older trope to explain what he means: a template.

  Think, he tells the reader, of an elaborate Currier and Ives etching, an image of a winter scene, cut into “a thick metal slab,” which is then covered by ink and transferred onto paper. “Genes first, then early interaction with cultural experience, etch a pattern that influences thinking and behavior.”48 This is not all that clear. If genes and early cultural experience are doing the etching, as the grammatical logic of the sentence implies, then both genes and early experience are part of that other metaphor: hardwiring. Hardwiring apparently explains why we don’t risk becoming anarchists even if we miss the lessons our parents are supposed to teach us, although wouldn’t those lessons be part of “early interaction with cultural experience”? For Tancredi, “hardwired” seems to equal “biological.” But biological processes do not necessarily mean inborn, innate, or determined.

  Experience happens to and in a body. And experience becomes that body unless there is a separate sphere, the mind, floating above the body and the brain, which stores experience in a separate mind pocket inside or beyond our gray matter. The letters of the alphabet and the words they form, numbers and their equations, laws and rules, are not biological, it is true. They are abstractions, symbols, but once they enter us, they become part of our memory, which involves, at the very least, physiological processes. I learned to swim and now my body remembers how to do it without further instruction. I learned to read and now when I open a book I don’t think about deciphering the letters. The meanings of the words have become a part of my physiological reality. What then is nonbiological and biological in this metaphor of a template? What exactly is hardwired? Has Tancredi lost himself in a philosophical problem he fails to articulate or does “biology” for him simply mean something genetically programmed with a bit of early experience thrown in?

  The notion of a hardwired trait is often linked to a specific brain region that has a particular function, not unlike a carburetor in a car. As with genes, these regions may be understood (or misunderstood) as more and less fixed entities. To use another metaphor, each part of the brain is like a country on a map with secure or fluid borders. “Scientists Discover Moral Compass in the Brain Which Can Be Controlled by Magnets” ran a headline in the Daily Mail. The moral compass, the reader is told, “is located right behind the right ear in the brain.”49 According to the journalist, the right temporoparietal junction (RTPJ) is the brain’s special moral area. The RTPJ has been associated with perception and attention, aspects of memory, with self-other “processing” and theory of mind (the ability to imagine other people’s internal states), with conversion disorders or hysteria (for example, a paralyzed arm that cannot be explained through visible neurological damage), with out-of-body experiences (the rape victim who floats up and out of herself or himself to witness the violence from above), and with multisensory integration for self-and-other experiences. That the RTPJ is a candidate brain region for our moral compass seems dubious.50 It would be far more accurate to say that because morality necessarily involves our relations to other people—and research has linked the temporo-parietal junction to a host of psychological states that involve perception, attention, self and other, or the self experienced as an other—this region of the brain appears to be involved in, among other things, what we call ethical understanding. I am the first to acknowledge that this circumspect sentence would make a bad headline.

  Neurologists have long known that damage to various parts of the brain can create particular kinds of losses. Injury to prefrontal areas of the brain, for example, may alter one’s personality, turning the once phlegmatic and considerate person into an impulsive, even violent being. Hippocampal lesions can bring severe memory problems. There seems to be no question that areas in the human brain can be linked to specific losses and therefore to specific functions. And yet, individuals may have lesions that appear to be identical and have very different symptoms. This remains mysterious. Every brain, like every nose and every person, is different. Broca’s area in the inferior frontal gyrus, for example, is named for the scientist and physician Paul Broca, who in 1861 declared that his autopsy findings for a patient named Leborgne (still called “Tan” in the neurological literature because the man repeatedly uttered this meaningless syllable) confirmed that the faculty for articulate language was located in the brain’s frontal lobe. By 1865, he had limited the faculty to the left frontal lobe. The left hemisphere is now acknowledged to be dominant for language in most, but not all, people.

  More recently, however, Broca’s area, which overlaps with the ventral premotor cortex, has been linked to other functions. It has been correlated with some aspects of memory, to listening and understanding music, and to motor functions, such as complex hand movements and other forms of sensorimotor learning.51 I mention this simply to demonstrate that boundaries in the brain do not appear to be hard and fast and that specific regions are linked to more than a single function, particularly in the brain’s cortex. A simple one-to-one correspondence between, say, language comprehension (the sentence you are reading now) and a discrete area in your brain is not a useful way to think about language and the brain.

  The location debates are old. Unlike Broca, the English neurologist John Hughlings Jackson (1835–1911) did not believe that language could be neatly separated from other cerebral functions. In “On the Nature of the Duality of the Brain,” Hughlings Jackson wrote, “To locate the damage which destroys speech and to locate speech are two different things.”52 For Hughlings Jackson, the nervous system was an organ for movement, including the most nuanced, voluntary movements of speech. He found the idea of brain geography with circumscribed neuroanatomical regions ridiculous. Sigmund Freud, who wrote a book about the neurological disorder aphasia before he published his psychoanalytic works, followed Hughlings Jackson on this question. It is not inaccurate to say that both Broca and Hughlings Jackson were right. There seems to be specialization in the brain, but it isn’t isolated, and it is never s
tatic. Synaptic connectivity is immense, and the number of studies on the relations among close and distant areas of the brain has increased significantly in recent years. In a paper in Brain Connectivity in 2011, Karl Friston noted that “a great deal of brain mapping is concerned with functional segregation and the localization of function. However, last year the annual increase in publications on connectivity surpassed the yearly increase in publications on activations per se.”53 Friston suggests the scales are tipping. Connectivity is replacing locationism as the focus of interest.

  The best historical overview of the locationist/antilocationist debate about the brain I have read is by the Russian neurologist A. R. Luria in his book Higher Cortical Functions in Man (1962). After explaining how both the locationists and antilocationists since the Greeks had made fundamental contributions to the understanding of the brain, Luria notes a common error he calls a “psychomorphological” feature of both theories: “They both look upon mental functions as phenomena to be directly correlated with the brain structure without intermediate physiological analysis.”54 Luria’s critique here is of automatic reduction—human morality, for example, is reduced without mediation to “circumscribed or extensive areas of the brain.”55 Why is such a reduction uncalled for?

  Let me give a personal example. Last year I was invited to an academic conference where I delivered a paper. I listened to one talk after another during the three-day conference, but only one paper truly irritated me. Not only was the speaker’s argument simplistic, he hopped over every bit of evidence in a long history of scholarship that did not support his views. I raised my hand. He called on me, and I gave a brief but sharp critique of the paper and then asked a pointed rhetorical question. Immediately afterward, I experienced mingled feelings of triumph and guilt, triumph because my barbs had been on point and guilt because I had clearly flustered and embarrassed the man. Exactly how does this moral dilemma and its accompanying feelings relate to my brain function, either localized or connective? Luria is not arguing for a psychological realm as wholly distinct from a physiological realm. He is not saying that my psyche is floating over and above my body and that this floating substance, mind, has to be taken into account. His argument is a materialist one.

  This is crucial: Can my mixed feelings be lifted out of the context of where I am and to whom I am speaking? Can they be lifted out of my culture and my personal history and my experiences with others without losing important elements of what is happening in my brain itself? I had read a lot on that man’s subject, and I remembered what I had read, not word by word, of course, but more than enough to feel qualified to puncture his presentation of the material. Remembering and forgetting are functions of a brain, but there is no memory or forgetting without a past, no memory or forgetting without others in that past, and those memories are consolidated in the brain by emotion, and my emotions also have a history that affects how I feel now. Patterns of emotional response are coded in the nervous system through my experiences. My RTPJ might well have been activated on a brain scan if someone had put me into an fMRI machine the moment after I made my little speech, but does that tell us everything about what happened to me or only a small part?

  Despite the way “the brain” is often presented in the media, it is not a precut jigsaw puzzle with a piece for morality and a piece for memory and a piece for sex. The human brain is a dynamic organ inside a person’s body that remains in continual interaction with what lies beyond that body. In other words, a brain must also be seen in relation to what lies beyond it, in which and through which it functions. Nevertheless, there are regions of the brain that for most people are involved in the same processes, and brains are not infinitely malleable organs that are made exclusively by “experience.” Isn’t it justifiable, then, to turn my subjective experience of attacking a paper, one we usually call psychological, into the objective terms of synapses and neurochemicals, what we usually call physiological? Are they the same or are they different? Are they one or are they two?

  How one answers these questions depends on what one believes about the “mind” and the “body.” Not knowing what he thinks about psyche and soma explains why the psychiatrist Tancredi found himself tangled up with “biological” and “hardwired” as synonyms and his additional reference to early experience. The question is: Would a perfect description of the brain processes involved in my indignant, then somewhat guilty, reaction at the conference suffice as an explanation of my moral feelings and, if not, why not? Luria suggests that an intermediate analysis of physiological processes is necessary. This understanding of the problem also involves questions of boundaries and semantics.

  After all, “morality” is a word, an abstract symbolic representation in English made up of eight letters to signify a host of human interactions that involve attachments to other people, internal ideas of right and wrong that also exist as external social norms in the culture, our actual behaviors toward others, and private feelings of guilt and satisfaction. There is no question that the way such interactions are structured and understood vary enormously from culture to culture. It is also true that all human societies have taboos, punishments, and rituals intended to order relations among their members. Luria is pointing to levels of complexity that cannot be reduced to a spot in the brain behind the human left ear or even to an infinitely more complex connection among multiple brain areas because it is not clear that such a reduction is justified. Luria was profoundly aware of the roles culture, language, thought, and reflection play in human neurophysiology.

  In terms of morality, one may want to ask, if moral arrangements are by their very nature interpersonal or intersubjective—that is, they must involve more than one person and therefore more than one brain—is it reasonable to identify morality in the brain of any single individual? Could we have morality without other people? Is it possible to posit an individual person without a relation to another person? A child who is locked up after birth and fed in the dark does not become properly “human.” Runts in a litter usually die. Sadly, human cases of neglect have been discovered and studied. Neglected and deprived children suffer from various problems, including language deficits.56 Are we not dependent on others to be born, grow up, and eventually think moral thoughts? What are the minimal circumstances needed to produce a “moral” person? And won’t the morality of that person be determined by where she or he lives—in the United States, China, Iran, Congo, or New Guinea? Is this a description of the nature/nurture division? Even if we accepted the division, what would nature look like without nurture? Do not factors beyond my own brain need to be considered to truly understand that same brain and the mingled emotions that occurred after my verbal darts were fired at the conference?

  Nature/Nurture: Minds and Pop Culture

  As Whitehead and Kuhn pointed out, such philosophical nuances often disappear among scientists themselves, who fail to examine the foundation of the house they are busy building. In popular science journalism, which comes to us by way of books, newspapers, TV, and the Internet, the houses presented to us are more than likely to have no foundations. The pegs and ropes holding up the landscape are missing. We are treated to descriptions of the brain as if the answers have all been given and no philosophical quandaries are involved. In Proust Was a Neuroscientist, the science writer and journalist Jonah Lehrer devotes a chapter to Stravinsky and explains, “While human nature largely determines how we hear the notes, it is nurture that lets us hear the music.”57 The distinction I believe Lehrer wishes to make is that while most of us can hear sounds even as fetuses, we have to learn to listen to Stravinsky, get used to his sounds, the same sounds that shocked many, but not all, of his early listeners. This seems reasonable enough.

  How this relates to the nature/nurture divide is another matter. Lehrer’s notes/music sentence is preceded by references to brain research. The reader is asked, “Who is in charge of our sensations?” His answer: “Experience.” The philosophical and semantic issues here are significant.
How is experience in charge? How far back does experience go? If a fetus develops sensory capacities in utero, are we not born with bodily sensations? A newborn already has developed senses of touch and smell, for example. “Learning,” he continues, “is largely the handiwork of dopamine, which modulates the cellular mechanisms underlying plasticity.” “But dopamine,” he adds, “has a dark side. When the dopamine system is unbalanced, the result is schizophrenia. If dopamine neurons can’t correlate their firing with outside events, the brain is unable to make cogent associations.”58 Like Lehrer’s “experience,” dopamine neurons appear as thinking subjects, active beings that correlate inside and outside.

  Dopamine has been associated with brain plasticity. Two years after Lehrer’s book was published in 2007, the authors of a paper in Klinische Neurophysiologie wrote, “In humans and animals, dopamine improves learning and memory formation. The neurophysiological foundation for this beneficial effect might be a focusing effect of dopamine, and thus an improvement of neuroplasticity. Knowledge about the effects of dopamine on neuroplasticity in humans is scarce”59 (my italics). There is a hypothesis that dopamine is involved in schizophrenia, especially its psychotic symptoms—hearing voices and delusions—but much remains to be understood. The illness has also been related to glutamate, to serotonin, to possible genetic influences, to a long-standing hypothesis that there may be some injury during birth. Some of its symptoms have been associated with a part of the brain—the insula—and to a progressive loss of gray matter in the brain. But why these physiological changes take place is unknown. To write that dopamine’s “dark side” results in schizophrenia is presenting a hypothesis as causal fact.60

 

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