by Adam Gopnik
Science;Neuroscience;Robert A. Burton;“A Skeptic’s Guide to the Mind”;Sally Satel;Scott O. Lilienfeld;“Brainwashed: The Seductive Appeal of Mindless Neuro-Science”Good myths turn on simple pairs— God and Lucifer, Sun and Moon, Jerry and George—and so an author who makes a vital duo is rewarded with a long-lived audience. No one in 1900 would have thought it possible that a century later more people would read Conan Doyle’s Holmes and Watson stories than anything of George Meredith’s, but we do. And so Gene Roddenberry’s “Star Trek,” despite the silly plots and the cardboard-seeming sets, persists in its many versions because it captures a deep and abiding divide. Mr. Spock speaks for the rational, analytic self who assumes that the mind is a mechanism and that everything it does is logical, Captain Kirk for the belief that what governs our life is not only irrational but inexplicable, and the better for being so. The division has had new energy in our time: we care most about a person who is like a thinking machine at a moment when we have begun to have machines that think. Captain Kirk, meanwhile, is not only a Romantic, like so many other heroes, but a Romantic on a starship in a vacuum in deep space. When your entire body is every day dissolved, reënergized, and sent down to a new planet, and you still believe in the ineffable human spirit, you have really earned the right to be a soul man.
Writers on the brain and the mind tend to divide into Spocks and Kirks, either embracing the idea that consciousness can be located in a web of brain tissue or debunking it. For the past decade, at least, the Spocks have been running the Enterprise: there are books on your brain and music, books on your brain and storytelling, books that tell you why your brain makes you want to join the Army, and books that explain why you wish that Bar Refaeli were in the barracks with you. The neurological turn has become what the “cultural” turn was a few decades ago: the all-purpose non-explanation explanation of everything. Thirty years ago, you could feel loftily significant by attaching the word “culture” to anything you wanted to inspect: we didn’t live in a violent country, we lived in a “culture of violence”; we didn’t have sharp political differences, we lived in a “culture of complaint”; and so on. In those days, Time, taking up the American pursuit of pleasure, praised Christopher Lasch’s “The Culture of Narcissism”; now Time has a cover story on happiness and asks whether we are “hardwired” to pursue it.
Myths depend on balance, on preserving their eternal twoness, and so we have on our hands a sudden and severe Kirkist backlash. A series of new books all present watch-and-ward arguments designed to show that brain science promises much and delivers little. They include “A Skeptic’s Guide to the Mind” (St. Martin’s), by Robert A. Burton; “Brainwashed: The Seductive Appeal of Mindless Neuro-Science” (Basic), by Sally Satel and Scott O. Lilienfeld; and “Neuro: The New Brain Sciences and the Management of the Mind” (Princeton), by a pair of cognitive scientists, Nikolas Rose and Joelle M. Abi-Rached.
from the issuecartoon banke-mail this.“Bumpology” is what the skeptical wit Sydney Smith, writing in the eighteen-twenties, called phrenology, the belief that the shape of your skull was a map of your mind. His contemporary heirs rehearse, a little mordantly, failed bits of Bumpology that indeed seem more like phrenology than like real psychology. There was the left-right brain split, which insisted on a far neater break within our heads (Spock bits to the left, Kirk bits to the right) than is now believed to exist. The skeptics revisit the literature on “mirror neurons,” which become excited in the frontal lobes of macaque monkeys when the monkeys imitate researchers, and have been used to explain the origins of human empathy and sociability. There’s no proof that social-minded Homo sapiens has mirror neurons, while the monkeys who certainly do are not particularly social. (And, if those neurons are standard issue, then they can’t be very explanatory of what we mean by empathy: Bernie Madoff would have as many as Nelson Mandela.)
It turns out, in any case, that it’s very rare for any mental activity to be situated tidily in one network of neurons, much less one bit of the brain. When you think you’ve located a function in one part of the brain, you will soon find that it has skipped town, like a bail jumper. And all of the neuro-skeptics argue for the plasticity of our neural networks. We learn and shape our neurology as much as we inherit it. Our selves shape our brains at least as much as our brains our selves.
Each author, though, has a polemical project, something to put in place of mere Bumpology. (People who write books on indoor plumbing seldom feel obliged to rival Vitruvius as theorists of architecture, but it seems that no one can write about one neuron without explaining all thought.) “Brainwashed” is nervously libertarian; Satel is a scholar at the American Enterprise Institute, and she and Lilienfeld are worried that neuroscience will shift wrongdoing from the responsible individual to his irresponsible brain, allowing crooks to cite neuroscience in order to get away with crimes. This concern seems overwrought, copping a plea via neuroscience not being a significant social problem. Burton, a retired medical neurologist, seems anxious to prove himself a philosopher, and races through a series of arguments about free will and determinism to conclude that neuroscience doesn’t yet know enough and never will. Minds give us the illusion of existing as fixed, orderly causal devices, when in fact they aren’t. Looking at our minds with our minds is like writing a book about hallucinations while on LSD: you can’t tell the perceptual evidence from your own inner state. “The mind is and will always be a mystery,” Burton insists. Maybe so, and yet we’re perfectly capable of probing flawed equipment with flawed equipment: we know that our eyes have blind spots, even as we look at the evidence with them, and we understand all about the dog whistles we can’t hear. Since in the past twenty-five years alone we’ve learned a tremendous amount about minds, it’s hard to share the extent of his skepticism. Psychology is an imperfect science, but it’s a science.
In “Neuro,” Rose and Abi-Rached see the real problem: neuroscience can often answer the obvious questions but rarely the interesting ones. It can tell us how our minds are made to hear music, and how groups of notes provoke neural connections, but not why Mozart is more profound than Manilow. Courageously, they take on, and dismiss, the famous experiments by Benjamin Libet that seem to undermine the idea of free will. For a muscle movement, Libet showed, the brain begins “firing”—choosing, let’s say, the left joystick rather than the right—milliseconds before the subject knows any choice has been made, so that by the time we think we’re making a choice the brain has already made it. Rose and Abi-Rached are persuasively skeptical that “this tells us anything about the exercise of human will in any of the naturally occurring situations where individuals believe they have made a conscious choice—to take a holiday, choose a restaurant, apply for a job.” What we mean by “free will” in human social practice is just a different thing from what we might mean by it in a narrower neurological sense. We can’t find a disproof of free will in the indifference of our neurons, any more than we can find proof of it in the indeterminacy of the atoms they’re made of.
A core objection is that neuroscientific “explanations” of behavior often simply re-state what’s already obvious. Neuro-enthusiasts are always declaring that an MRI of the brain in action demonstrates that some mental state is not just happening but is really, truly, is-so happening. We’ll be informed, say, that when a teen-age boy leafs through the Sports Illustrated swimsuit issue areas in his brain associated with sexual desire light up. Yet asserting that an emotion is really real because you can somehow see it happening in the brain adds nothing to our understanding. Any thought, from Kiss the baby! to Kill the Jews!, must have some route around the brain. If you couldn’t locate the emotion, or watch it light up in your brain, you’d still be feeling it. Just because you can’t see it doesn’t mean you don’t have it. Satel and Lilienfeld like the term “neuroredundancy” to “denote things we already knew without brain scanning,” mockingly citing a researcher who insists that “brain imaging tells us that post-traumatic stress disorder (PTSD) is a ‘real disorder.’ ” The brain scan, like the word “wired,” adds a false gloss of scientific certainty to what we already thought. As with the old invocation of “culture,” it’s intended simply as an intensifier of the obvious.
Phrenology, the original Bumpology, at least had the virtue of getting people to think about “cortical location,” imagining, for the first time, that the brain might indeed be mapped into areas. Bumpology brought a material order, however factitious, to a metaphysical subject. In the same way, even the neuro-skeptics seem to agree that modern Bumpology remains an important corrective to radical anti-Bumpology: to the kind of thinking that insists that brains don’t count at all and cultures construct everything; that, given the right circumstances, there could be a human group with six or seven distinct genders, each with its own sexuality; that there is a possible human society in which very old people would be regarded as attractive and nubile eighteen-year-olds not; and still another where adolescent children would be noted for their rigorous desire to finish recently commenced tasks. How impressive you find modern pop Bumpology depends in part on whether you believe that there are a lot of people who still think like that.
For all the exasperations of neurotautology, there’s a basic, arresting truth to neo-Bumpology. In a new, belligerently pro-neuro book, “The Anatomy of Violence: The Biological Roots of Crime” (Pantheon), Adrian Raine, a psychology professor at the University of Pennsylvania, discusses a well-studied case in which the stepfather of an adolescent girl, with no history of pedophilia, began to obsess over child pornography and then to molest his stepdaughter. He was arrested, arraigned, and convicted. Then it emerged that he had a tumor, pressing on the piece of the brain associated with social and sexual inhibitions. When it was removed, the wayward desires vanished. Months of normality ensued, until the tumor began to grow back and, with it, the urges.
Now, there probably is no precise connection between the bit of the brain the tumor pressed on and child lust. The same bit of meat-matter pressing on the same bit of brain in some other head might have produced some other transgression—in the head of a Lubavitcher, say, a mad desire to eat prosciutto. But it would still be true that what we think of as traditionally deep matters of guilt and temptation and taboo, the material of Sophocles and Freud, can be flicked on and off just by physical pressure. You have to respect the power of the meat to change the morals so neatly.
In one sense, this is more neuro-redundancy. Charting a path between these two truths is the philosopher Patricia S. Churchland’s project in “Touching a Nerve: The Self as Brain” (Norton), a limited defense of the centrality of neuro. She is rightly contemptuous of the invocation of “scientism” to dismiss the importance of neuroscience to philosophy, seeing that resistance as identical to the Inquisition’s resistance to Galileo, or the seventeenth century’s to Harvey’s discovery of the pumping heart:
This is the familiar strategy of let’s pretend. Let’s believe what we prefer to believe. But like the rejection of the discovery that Earth revolves around the sun, the let’s pretend strategy regarding the heart could not endure very long. . . . Students reading the history of this period may be as dumbfounded regarding our resistance to brain science as we are now regarding the seventeenth-century resistance to the discovery that the heart is a meat pump.
Humanism not only has survived each of these sequential demystifications; they have made it stronger by demonstrating the power of rational inquiry on which humanism depends. Every time the world becomes less mysterious, nature becomes less frightening, and the power of the mind to grasp reality more sure. A constant reduction of mystery to matter, a belief that we can name natural rules we didn’t make—that isn’t scientism. That’s science.
Yet Churchland also makes beautifully clear how complex and contingent the simplest brain business is. She discusses whether the hormone testosterone makes men angry. The answer even to that off-on question is anything but straightforward. Testosterone counts for a lot in making men mad, but so does the “stress” hormone cortisol, along with the “neuromodulator” serotonin, which affects whether the aggression is impulsive or premeditated, and the balance between all these things is affected by “other hormones, other neuromodulators, age and environment.”
So this question, like any other about neurology, turns out to be both simply mechanical and monstrously complex. Yes, a hormone does wash through men’s brains and makes them get mad. But there’s a lot more turning on than just the hormone. For a better analogy to the way your neurons and brain chemistry run your mind, you might think about the way the light switch runs the lights in your living room. It’s true that the light switch in the corner turns the lights on in the living room. Nor is that a trivial observation. How the light switch gets wired to the bulb, how the bulb got engineered to be luminous—all that is an almost miraculously complex consequence of human ingenuity. But at the same time the light switch on the living-room wall is merely the last stage in a long line of complex events that involve waterfalls and hydropower and surge protectors and thousands of miles of cables and power grids. To say the light switch turns on the living-room light is both true—vitally true, if you don’t want to bang your shins on the sofa sneaking home in the middle of the night—and wildly misleading.
It’s perfectly possible, in other words, to have an explanation that is at once trivial and profound, depending on what kind of question you’re asking. The strength of neuroscience, Churchland suggests, lies not so much in what it explains as in the older explanations it dissolves. She gives a lovely example of the panic that we feel in dreams when our legs refuse to move as we flee the monster. This turns out to be a straightforward neurological phenomenon: when we’re asleep, we turn off our motor controls, but when we dream we still send out signals to them. We really are trying to run, and can’t. If you feel this, and also have the not infrequent problem of being unable to distinguish waking and dreaming states, you might think that you have been paralyzed and kidnapped by aliens.
There are no aliens; there is not even a Freudian wave of guilt driving the monster. It’s just those neuromotor neurons, making the earth sticky. The best thing for people who have recurrent nightmares of this kind is to get more REM rest. “Get more sleep,” Churchland remarks. “It works.” Neurology should provide us not with sudden explanatory power but with a sense of relief from either taking too much responsibility for, or being too passive about, what happens to us. Autism is a wiring problem, not a result of “refrigerator mothers.” Schizophrenia isn’t curable yet, but it looks more likely to be cured by getting the brain chemistry right than by finding out what traumatized Gregory Peck in his childhood. Neuroscience can’t rob us of responsibility for our actions, but it can relieve us of guilt for simply being human. We are in better shape in our mental breakdowns if we understand the brain breakdowns that help cause them. This is a point that Satel and Lilienfeld, in their eagerness to support a libertarian view of the self as a free chooser, get wrong. They observe of one “brilliant and tormented” alcoholic that she, not her heavy drinking, was responsible for her problems. But, if we could treat the brain circuitry that processes the heavy drinking, we might very well leave her just as brilliant and tormented as ever, only not a drunk. (A Band-Aid, as every parent knows, is an excellent cure whenever it’s possible to use one.)
The really curious thing about minds and brains is that the truth about them lies not somewhere in the middle but simultaneously on both extremes. We know already that the wet bits of the brain change the moods of the mind: that’s why a lot of champagne gets sold on Valentine’s Day. On the other hand, if the mind were not a high-level symbol-managing device, flower sales would not rise on Valentine’s Day, too. Philosophy may someday dissolve into psychology and psychology into neurology, but since the lesson of neuro is that thoughts change brains as much as brains thoughts, the reduction may not reduce much that matters. As Montaigne wrote, we are always double in ourselves. Or, as they say on the Enterprise, it takes all kinds to run a starship. ♦
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