A Woman Looking at Men Looking at Women: Essays on Art, Sex, and the Mind
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M’s idea that a psychological sense of entitlement can be directly attributed to genes is not borne out by genetic research, which is not the same as saying there is no hereditary dynamic, but rather that the road from genes to an organism’s structure is tortuous and depends on many factors, including how an animal is cared for in early life. Nevertheless the “idea” of genes as a “program” persists. The biologist François Jacob launched the metaphor in 1970: “The programme is a model borrowed from electronic computers. It equates the genetic material of an egg with the magnetic tape of a computer.”42 This equation assumes that, as in a computer, the whole logic is contained in the DNA sequence. As early as the 1950s, the geneticist Barbara McClintock uncovered evidence that genes were not a static linear message inscribed in the sequence of DNA.43 All of this is well known and has been presented repeatedly in many ways by many people doing genetic research as well as by philosophers of science.
And yet, the computer metaphor is by no means dead among geneticists. I repeatedly run into references to hardware and software and programs when I read papers on the subject. There are people working in the field who cling to the metaphor and others who think the computer analogy has served its purpose and should be dropped. As Keller points out, most metaphors contain an inherent ambiguity that can spur research but at the same time limit it because just as the metaphor opens the scientist to new ways of seeing, it may close off other visions it could not possibly contain. Unlike Jacob’s computer tape, which moves in one direction only and is the code for the organism’s features, the ball in Waddington’s landscape can roll in several directions depending on pegs, guys, and, my addition—the weather—all of which affect how the organism will turn out. Thinking without metaphors is impossible. Try doing it. You will soon find you are trapped. They are embedded in the nature of language itself, and language, as Vico believed, is at once a cultural and bodily phenomenon. Hobbes understood language to be essential to reasoning, and reasoning was logical and mathematical. Therefore it needed to be cleansed of all tropes.
What interests me here, however, is why certain metaphors are broadly appealing and others aren’t. I suspect many people prefer heroic, active Master Molecules, modeled on an image from computer technology, to dependent genes that can’t do anything without the cell around them, a picture that rather closely resembles our prenatal life inside our mothers. Perhaps clean, hard boundaries have a nice logical feeling and entangled interactions suggest something messier, perhaps even something less rational. One can’t help but be reminded of Princess Elisabeth noting that a vaporous body can interfere with, even erase, sound reasoning, so there must be some relation between the two. The borders, Dear Mr. Philosopher, can’t be quite as neat as you hope them to be.
Most of us like to be known as hardheaded thinkers rather than soft-minded dreamers, and we lean toward rigor, not imprecision. As I pointed out in another essay, in science, the word “squishy” is a synonym for muddle, and lurking under the adjective is the notion of the soft and feminine.44 On the other hand, rigidity can have negative connotations and flexibility positive ones. The initial understanding of DNA, a momentous discovery, certainly, was nevertheless shaped by a desire to present the findings in a form that was precise, not blurry, and this desire is a reflection of science itself and its need to fit nature into what Kuhn called conceptual boxes.
Brains: Hard or Soft?
What about hardwired brains? The metaphor was imported from engineering to mean a form of brain fixity, usually genetically determined, but the meaning of the word shifts depending on how it is used. The reference is to electronic wires or cables in a machine, such as the telephone, but also to the computer. In a computer, that which is hardwired is controlled by hardware, not software, and therefore cannot be changed by the user or programmer without difficulty. The contemporary term “hardwiring,” which resonates with the mechanistic thought of the seventeenth century, links the brain to a machine. The terminology is now ubiquitous, both inside science and outside it in popular culture.
A fairly conventional scientific meaning of hardwiring appears in John Dowling’s book The Great Brain Debate: Nature or Nurture? (2004). Addressing the plastic or malleable character of the human cortex, the most recently evolved part of the brain, Dowling explains that early hints of its ability to adapt to altered circumstances arrived through experiments with people who wore optical prisms that turned their worlds literally upside down. After a few days of this confounding vision, people’s eyes adjusted and they began to see normally again. When the prisms were removed, they reverted to seeing right-side up within a few hours. Dowling cites research that demonstrates this is not true for frogs. “Thus, cold-blooded vertebrates do seem to have a much more hardwired nervous system than mammals.”45 Note that the word is used not in absolute but in relative terms, not either/or but more and less. Frogs are harder-wired than people. Of course actual brains do not have wires or anything that looks like wires in them. But then, this particular metaphor has become dead or nearly dead through frequent use.
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 exp
erience 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 temporo-parietal 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 static. 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 emotio
nal 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.