Quiet

by Susan Cain

  “Functional, moderate guilt,” writes Kochanska, “may promote future altruism, personal responsibility, adaptive behavior in school, and harmonious, competent, and prosocial relationships with parents, teachers, and friends.” This is an especially important set of attributes at a time when a 2010 University of Michigan study shows that college students today are 40 percent less empathetic than they were thirty years ago, with much of the drop having occurred since 2000. (The study’s authors speculate that the decline in empathy is related to the prevalence of social media, reality TV, and “hyper-competitiveness.”)

  Of course, having these traits doesn’t mean that sensitive children are angels. They have selfish streaks like everyone else. Sometimes they act aloof and unfriendly. And when they’re overwhelmed by negative emotions like shame or anxiety, says Aron, they can be positively oblivious of other people’s needs.

  But the same receptivity to experience that can make life difficult for the highly sensitive also builds their consciences. Aron tells of one sensitive teen who persuaded his mother to feed a homeless person he’d met in the park, and of another eight-year-old who cried not only when she felt embarrassed, but also when her peers were teased.

  We know this type of person well from literature, probably because so many writers are sensitive introverts themselves. He “had gone through life with one skin fewer than most men,” the novelist Eric Malpass writes of his quiet and cerebral protagonist, also an author, in the novel The Long Long Dances. “The troubles of others moved him more, as did also the teeming beauty of life: moved him, compelled him, to seize a pen and write about them. [He was moved by] walking in the hills, listening to a Schubert impromptu, watching nightly from his armchair the smashing of bone and flesh that made up so much of the nine o’clock news.”

  The description of such characters as thin-skinned is meant metaphorically, but it turns out that it’s actually quite literal. Among the tests researchers use to measure personality traits are skin conductance tests, which record how much people sweat in response to noises, strong emotions, and other stimuli. High-reactive introverts sweat more; low-reactive extroverts sweat less. Their skin is literally “thicker,” more impervious to stimuli, cooler to the touch. In fact, according to some of the scientists I spoke to, this is where our notion of being socially “cool” comes from; the lower-reactive you are, the cooler your skin, the cooler you are. (Incidentally, sociopaths lie at the extreme end of this coolness barometer, with extremely low levels of arousal, skin conductance, and anxiety. There is some evidence that sociopaths have damaged amygdalae.)

  Lie detectors (polygraphs) are partially skin conductance tests. They operate on the theory that lying causes anxiety, which triggers the skin to perspire imperceptibly. When I was in college, I applied for a summer job as a secretary at a large jewelry company. I had to take a lie detector test as part of the application process. The test was administered in a small, dingily lit room with linoleum floors, by a thin, cigarette-puffing man with pocked yellow skin. The man asked me a series of warm-up questions: my name, address, and so on, to establish my baseline level of skin conductance. Then the questions grew more probing and the examiner’s manner harsher. Had I been arrested? Had I ever shoplifted? Had I used cocaine? With this last question my interrogator peered at me intently. As it happens, I never had tried cocaine. But he seemed to think I had. The accusing look on his face was the equivalent of the old policeman’s trick where they tell the suspect that they have the damning evidence and there’s no point denying it.

  I knew the man was mistaken, but I still felt myself blush. And sure enough, the test came back showing I’d lied on the cocaine question. My skin is so thin, apparently, that it sweats in response to imaginary crimes!

  We tend to think of coolness as a pose that you strike with a pair of sunglasses, a nonchalant attitude, and drink in hand. But maybe we didn’t choose these social accessories at random. Maybe we’ve adopted dark glasses, relaxed body language, and alcohol as signifiers precisely because they camouflage signs of a nervous system on overdrive. Sunglasses prevent others from seeing our eyes dilate with surprise or fear; we know from Kagan’s work that a relaxed torso is a hallmark of low reactivity; and alcohol removes our inhibitions and lowers our arousal levels. When you go to a football game and someone offers you a beer, says the personality psychologist Brian Little, “they’re really saying hi, have a glass of extroversion.”

  Teenagers understand instinctively the physiology of cool. In Curtis Sittenfeld’s novel Prep, which explores the adolescent social rituals of boarding-school life with uncanny precision, the protagonist, Lee, is invited unexpectedly to the dorm room of Aspeth, the coolest girl in school. The first thing she notices is how physically stimulating Aspeth’s world is. “From outside the door, I could hear pounding music,” she observes. “White Christmas lights, currently turned on, were taped high up along all the walls, and on the north wall they’d hung an enormous orange and green tapestry.… I felt overstimulated and vaguely irritated. The room I shared with [my roommate] seemed so quiet and plain, our lives seemed so quiet and plain. Had Aspeth been born cool, I wondered, or had someone taught her, like an older sister or a cousin?”

  Jock cultures sense the low-reactive physiology of cool, too. For the early U.S. astronauts, having a low heart rate, which is associated with low reactivity, was a status symbol. Lieutenant Colonel John Glenn, who became the first American to orbit the Earth and would later run for president, was admired by his comrades for his supercool pulse rate during liftoff (only 110 beats per minute).

  But physical lack of cool may be more socially valuable than we think. That deep blush when a hard-bitten tester puts his face an inch from yours and asks if you’ve ever used cocaine turns out to be a kind of social glue. In a recent experiment, a team of psychologists led by Corine Dijk asked sixty-odd participants to read accounts of people who’d done something morally wrong, like driving away from a car crash, or something embarrassing, like spilling coffee on someone. The participants were shown photographs of the wrongdoers, who had one of four different facial expressions: shame or embarrassment (head and eyes down); shame/embarrassment plus a blush; neutral; or neutral with a blush. Then they were asked to rate how sympathetic and trustworthy the transgressors were.

  It turned out that the offenders who blushed were judged a lot more positively than those who didn’t. This was because the blush signified concern for others. As Dacher Keltner, a psychologist at the University of California, Berkeley, who specializes in positive emotions, put it to the New York Times, “A blush comes online in two or three seconds and says, ‘I care; I know I violated the social contract.’ ”

  In fact, the very thing that many high-reactives hate most about blushing—its uncontrollability—is what makes it so socially useful. “Because it is impossible to control the blush intentionally,” Dijk speculates, blushing is an authentic sign of embarrassment. And embarrassment, according to Keltner, is a moral emotion. It shows humility, modesty, and a desire to avoid aggression and make peace. It’s not about isolating the person who feels ashamed (which is how it sometimes feels to easy blushers), but about bringing people together.

  Keltner has tracked the roots of human embarrassment and found that after many primates fight, they try to make up. They do this partly by making gestures of embarrassment of the kind we see in humans—looking away, which acknowledges wrongdoing and the intention to stop; lowering the head, which shrinks one’s size; and pressing the lips together, a sign of inhibition. These gestures in humans have been called “acts of devotion,” writes Keltner. Indeed, Keltner, who is trained in reading people’s faces, has studied photos of moral heroes like Gandhi and the Dalai Lama and found that they feature just such controlled smiles and averted eyes.

  In his book, Born to Be Good, Keltner even says that if he had to choose his mate by asking a single question at a speed-dating event, the question he would choose is: “What was your last embarrassing expe
rience?” Then he would watch very carefully for lip-presses, blushing, and averted eyes. “The elements of the embarrassment are fleeting statements the individual makes about his or her respect for the judgment of others,” he writes. “Embarrassment reveals how much the individual cares about the rules that bind us to one another.”

  In other words, you want to make sure that your spouse cares what other people think. It’s better to mind too much than to mind too little.

  No matter how great the benefits of blushing, the phenomenon of high sensitivity raises an obvious question. How did the highly sensitive manage to survive the harsh sorting-out process of evolution? If the bold and aggressive generally prevail (as it sometimes seems), why were the sensitive not selected out of the human population thousands of years ago, like tree frogs colored orange? For you may, like the protagonist of The Long Long Dances, be moved more deeply than the next person by the opening chords of a Schubert impromptu, and you may flinch more than others at the smashing of bone and flesh, and you may have been the sort of child who squirmed horribly when you thought you’d broken someone’s toy, but evolution doesn’t reward such things.

  Or does it?

  Elaine Aron has an idea about this. She believes that high sensitivity was not itself selected for, but rather the careful, reflective style that tends to accompany it. “The type that is ‘sensitive’ or ‘reactive’ would reflect a strategy of observing carefully before acting,” she writes, “thus avoiding dangers, failures, and wasted energy, which would require a nervous system specially designed to observe and detect subtle differences. It is a strategy of ‘betting on a sure thing’ or ‘looking before you leap.’ In contrast, the active strategy of the [other type] is to be first, without complete information and with the attendant risks—the strategy of ‘taking a long shot’ because the ‘early bird catches the worm’ and ‘opportunity only knocks once.’ ”

  In truth, many people Aron considers sensitive have some of the twenty-seven attributes associated with the trait, but not all of them. Maybe they’re sensitive to light and noise, but not to coffee or pain; maybe they’re not sensitive to anything sensory, but they’re deep thinkers with a rich inner life. Maybe they’re not even introverts—only 70 percent of sensitive people are, according to Aron, while the other 30 percent are extroverts (although this group tends to report craving more downtime and solitude than your typical extrovert). This, speculates Aron, is because sensitivity arose as a by-product of survival strategy, and you need only some, not all, of the traits to pull off the strategy effectively.

  There’s a great deal of evidence for Aron’s point of view. Evolutionary biologists once believed that every animal species evolved to fit an ecological niche, that there was one ideal set of behaviors for that niche, and that species members whose behavior deviated from that ideal would die off. But it turns out that it’s not only humans that divide into those who “watch and wait” and others who “just do it.” More than a hundred species in the animal kingdom are organized in roughly this way.

  From fruit flies to house cats to mountain goats, from sunfish to bushbaby primates to Eurasian tit birds, scientists have discovered that approximately 20 percent of the members of many species are “slow to warm up,” while the other 80 percent are “fast” types who venture forth boldly without noticing much of what’s going on around them. (Intriguingly, the percentage of infants in Kagan’s lab who were born high-reactive was also, you’ll recall, about twenty.)

  If “fast” and “slow” animals had parties, writes the evolutionary biologist David Sloan Wilson, “some of the fasts would bore everyone with their loud conversation, while others would mutter into their beer that they don’t get any respect. Slow animals are best described as shy, sensitive types. They don’t assert themselves, but they are observant and notice things that are invisible to the bullies. They are the writers and artists at the party who have interesting conversations out of earshot of the bullies. They are the inventors who figure out new ways to behave, while the bullies steal their patents by copying their behavior.”

  Once in a while, a newspaper or TV program runs a story about animal personalities, casting shy behavior as unseemly and bold behavior as attractive and admirable. (That’s our kind of fruit fly!) But Wilson, like Aron, believes that both types of animals exist because they have radically different survival strategies, each of which pays off differently and at different times. This is what’s known as the trade-off theory of evolution, in which a particular trait is neither all good nor all bad, but a mix of pros and cons whose survival value varies according to circumstance.

  “Shy” animals forage less often and widely for food, conserving energy, sticking to the sidelines, and surviving when predators come calling. Bolder animals sally forth, swallowed regularly by those farther up the food chain but surviving when food is scarce and they need to assume more risk. When Wilson dropped metal traps into a pond full of pumpkinseed fish, an event he says must have seemed to the fish as unsettling as a flying saucer landing on Earth, the bold fish couldn’t help but investigate—and rushed headlong into Wilson’s traps. The shy fish hovered judiciously at the edge of the pond, making it impossible for Wilson to catch them.

  On the other hand, after Wilson succeeded in trapping both types of fish with an elaborate netting system and carrying them back to his lab, the bold fish acclimated quickly to their new environment and started eating a full five days earlier than did their shy brethren. “There is no single best … [animal] personality,” writes Wilson, “but rather a diversity of personalities maintained by natural selection.”

  Another example of the trade-off theory of evolution is a species known as Trinidadian guppies. These guppies develop personalities—with astonishing speed, in evolutionary terms—to suit the microclimates in which they live. Their natural predators are pike. But some guppy neighborhoods, upstream of a waterfall for example, are pike-free. If you’re a guppy who grew up in such a charmed locale, then chances are you have a bold and carefree personality well suited to la dolce vita. In contrast, if your guppy family came from a “bad neighborhood” downstream from the waterfall, where pike cruise the waterways menacingly, then you probably have a much more circumspect style, just right for avoiding the bad guys.

  The interesting thing is that these differences are heritable, not learned, so that the offspring of bold guppies who move into bad neighborhoods inherit their parents’ boldness—even though this puts them at a severe disadvantage compared to their vigilant peers. It doesn’t take long for their genes to mutate, though, and descendants who manage to survive tend to be careful types. The same thing happens to vigilant guppies when the pike suddenly disappear; it takes about twenty years for their descendants to evolve into fish who act as if they haven’t a care in the world.

  The trade-off theory seems to apply equally to humans. Scientists have found that nomads who inherited the form of a particular gene linked to extroversion (specifically, to novelty-seeking) are better nourished than those without this version of the gene. But in settled populations, people with this same gene form have poorer nutrition. The same traits that make a nomad fierce enough to hunt and to defend livestock against raiders may hinder more sedentary activities like farming, selling goods at the market, or focusing at school.

  Or consider this trade-off: human extroverts have more sex partners than introverts do—a boon to any species wanting to reproduce itself—but they commit more adultery and divorce more frequently, which is not a good thing for the children of all those couplings. Extroverts exercise more, but introverts suffer fewer accidents and traumatic injuries. Extroverts enjoy wider networks of social support, but commit more crimes. As Jung speculated almost a century ago about the two types, “the one [extroversion] consists in a high rate of fertility, with low powers of defense and short duration of life for the single individual; the other [introversion] consists in equipping the individual with numerous means of self-preservation plus a low fertility r
ate.”

  The trade-off theory may even apply to entire species. Among evolutionary biologists, who tend to subscribe to the vision of lone individuals hell-bent on reproducing their own DNA, the idea that species include individuals whose traits promote group survival is hotly debated and, not long ago, could practically get you kicked out of the academy. But this view is slowly gaining acceptance. Some scientists even speculate that the evolutionary basis for traits like sensitivity is heightened compassion for the suffering of other members of one’s species, especially one’s family.

  But you don’t have to go that far. As Aron explains, it makes sense that animal groups depend on their sensitive members for survival. “Suppose a herd of antelope … has a few members who are constantly stopping their grazing to use their keen senses to watch for predators,” she writes. “Herds with such sensitive, watchful individuals would survive better, and so continue to breed, and so continue to have some sensitive individuals born in the group.”

  And why should it be any different for humans? We need our Eleanor Roosevelts as surely as grazing herds depend on their sensitive antelopes.

  In addition to “shy” and “bold” animals, and to “fast” and “slow” ones, biologists sometimes speak of the “hawk” and “dove” members of a given species. Great tit birds, for example, some of whom are much more aggressive than others, often act like case studies in an international relations class. These birds feed on beech tree nuts, and in years when nuts are scarce, the hawkish female birds do better, just as you’d expect, because they’re quick to challenge nut-eating competitors to a duel. But in seasons when there are plenty of beech nuts to go around, the female “doves”—who, incidentally, tend to make more attentive mothers—do better than the “hawks,” because the hawks waste time and bodily health getting into fights for no good reason.