50 Shades of gray matter
You’ve seen the headlines: This is your brain on God, envy, cocaine. And you’ve seen the evidence: slices of brain with Technicolor splotches lit up like the Las Vegas Strip.
On average, one new book about the brain appears every week. In universities, new disciplines of neuroeconomics, neuroaesthetics, and neurolaw are flourishing. “If Warhol were around today, he’d have a series of silkscreens dedicated to the cortex; the amygdala would hang alongside Marilyn Monroe,” one observer quipped.
It is easy to see why the brain is a hot commodity. As the organ of the self, it makes sense to think that understanding how the brain works can help us understand ourselves, repair our flaws, and perfect our nature.
Over the years, the public’s romance with the brain has blossomed thanks to the advent of brain imaging. This ingenious technique measures the activity of the brain, producing rainbow-hued representation of the neural landscape. As Tom Wolfe wrote of brain imaging in the mid-90s, “anyone who cares to get up early and catch a truly blinding 21st-century dawn will want to keep an eye on it.” Almost two decades later, we haven’t been able to look away.
Why the fixation? First, of course, there is the brain itself. More complex than any structure in the known cosmos, the brain is a masterwork of nature endowed with cognitive powers that far outstrip the capacity of any silicon machine built to emulate it. Containing roughly 80 billion brain cells, or neurons, each of which communicates with thousands of other neurons, the three-pound universe cradled between our ears has more connections than there are stars in the Milky Way.
Now combine this mystique with the simple fact that pictures—in this case, brain scans—are powerful. Of all our senses, vision is the most developed. As Galileo understood all too well, our eyes can deceive us. He wrote in his Dialogues of 1632 that the Copernican model of the heliocentric universe commits a “rape upon the senses”—it violates everything our eyes tell us.
The brain also holds the promise of objective truth. If the mind is ephemeral and amorphous, the brain is concrete. The field of psychology—the study of the mind—is “the Rodney Dangerfield of the sciences,” lamented the psychologist Keith Stanovich. It can’t get no respect. But invoke the frontal lobes, add a dash of dopamine, and watch even the softest science harden into knowledge that average people—and sometimes even scholars—take more seriously.
Consider, for example, the pleasures of love or chocolate or even schadenfreude. Everyone knows how great these things are, but somehow seeing the brain’s reward centers “light up” prompts many to regard the phenomena as somehow more authentic than other types of psychological information, a tendency that my colleague, the psychologist Scott Lilienfeld, and I call “neurocentrism.”
What’s more, brain scans do not yield unfiltered views of the mind in action. Instead, they depict areas of the brain that become more active (consume more oxygen, to be precise) when people perform tasks such as looking at pictures or problem solving. Combined with other data, such information can inform neuroscientists about the biological mechanisms that produce thoughts and emotions.
But inferring precisely what someone is thinking or feeling from a color-drenched scan is not in the cards –well, scans. Indeed, the psychologists Christopher Chabris and Daniel Simons have coined a term for titillating but spurious interpretations of brain images by the media, and even the occasional overzealous scientist: “brain porn.”
If the promise of neuroscience is to plumb human nature, will we learn that we aren’t really in charge of ourselves? From this view, human choice is just “what the brain does,” and since the brain is a material organ just like the spleen or liver, the behavior of a person is, in principle, as predictable as the orbit of a planet. This plunges us, ready or not, into the free-will debate—whether moral agency and responsibility can exist in a material world—and, more to the point, whether insights from neurobiology can resolve it.
As much as we might like brain science to be our guide, it won’t solve this age-old philosophical puzzle.
Practically speaking, however, seeing ourselves through the lens of the brain taps into the human desire to change for the better. A stream of books devoted to attaining goals, breaking unwanted habits, educating students more effectively, and boosting self-awareness summon the well-established capacity of brain cells to change though practice and experience.
So, here is a paradox. We are at once the victims of our neurochemistry and the agents of our self-improvement. Marc Lewis, the youthful protagonist of Memoirs of an Addicted Brain and now a neuroscientist, invokes the derangement in his dopamine-driven reward circuitry to explain why “addicts lose the mental muscle tone for self-direction, for resolve, for sobriety, for strength of character, and for decency itself.”
Regaining those capacities, however, does not happen through a dopamine-enhancing pill. Lewis may use the language of neuroscience, but the daily work of recovery is a human process pursued in the idiom of purposeful action, choice, and consequence.
Then there is the notion that neuroscience will illuminate the path to human flourishing. “The more we understand ourselves at the level of the brain,” the neuroscientist Sam Harris wrote in his 2010 book, The Moral Landscape: How Science Can Determine Human Values, “the more we will see that there are right and wrong answers to questions of human values.” If so, how? No less towering a figure than the neuroscientist Michael Gazzaniga hopes for a “brain-based philosophy of life” based on an ethics that is “built into our brains. A lot of suffering, war, and conflict could be eliminated if we could agree to live by them more consciously.”
Such expansiveness compels one to ask whether neuroscience is on the verge of becoming the new genetics, the latest in a string of theories from Freudianism to behaviorism to sociobiology to be conscripted as a comprehensive explanation of human nature.
The brain has even wandered into such unlikely redoubts as English departments, where professors debate whether scanning subjects’ brains as they read passages from Jane Austen novels represents (a) a fertile inquiry into the power of literature or (b) a desperate attempt to inject novelty into a field that has exhausted its romance with psychoanalysis and postmodernism. The latter seems the more likely explanation.
Literary scholars may speculate on the neural underpinnings of, say, empathy (e.g., mirror neurons) or theory of mind, but this can’t possibly reveal more about the interior life of the reader. It’s true that all subjective experience, from a frisson of fear to the sweetness of nostalgia, corresponds to physical events in the brain. But does it really help a reader—or a writer—to know, as one team of neuroscientists claims to have discovered, that the neural basis for love is “restricted to foci in the medial insula and the anterior cingulate cortex and, subcortically, in the caudate nucleus and the putamen, all bilaterally”?
It is only natural that advances in knowledge about the brain make people think more mechanistically about themselves. Still, mechanism is not meaning. The brain creates the mind through the actions of neurons and circuits, yes, but it cannot reveal its nuanced contents. Despite our romance with the brain, we make sense of ourselves and the world by thinking about desires, intentions, and actions. No matter how intricately scientists understand the brain, they won’t be able to answer why we sabotage ourselves—the question that, in some form or another, has launched a zillion therapy hours. It won’t compel us to adopt a new moral code or revamp our system of criminal justice.
Learning more about the brain will help unravel more about the knotty relationship between mind and brain; it will make deep inroads into treatments for diseases such as Alzheimer’s. But no matter how dazzling the fruits of inquiry or how ingeniously they are obtained, brain-based explanations of our longings, exploits, and foibles are sure to break our hearts.
Author Bio:Sally Satel is a psychiatrist and co-author of the new book Brainwashed: The Seductive Appeal of Mindless Neuroscience (Basic Books).