The Brain in the World

Early one morning in August 1997, Korean Air Flight 801 was heading for a landing at Guam Airport. There was a spate of heavy weather—which wouldn’t have been a problem in itself. But the airport’s guidance system was down, and the pilot was dog-tired, having been awake for nineteen hours straight. Even though he’d landed at this airport many times in the past, he forgot that there was a big hill blocking the approach to the runway. He flew the plane right into it, killing 228 people.

That was one of eight crashes over twenty years for Korean Air, which at the time held the worst safety record of any airline, as Malcolm Gladwell relates in his recent book Outliers. The consultant who came in to analyze the problem found a surprising reason for it: the Koreans’ cultural tendency to be extremely deferential to their superiors. Both the first officer and the flight engineer had recognized danger signs, but they couldn’t bring themselves to confront the pilot directly or take control of the plane.

The consultant’s analysis drew on the work of Geert Hofstede, a Dutch psychologist who spent many years analyzing business culture around the globe, assigning different countries a “power-distance index” (PDI) based on how much their citizens defer to those in power. Americans, having a low PDI, are accustomed to speaking frankly to superiors as the occasion demands. A study of the airline industry revealed that South Korea has the second highest PDI of any country in the world.

The problem went away when the consultant required everyone in Korean Air’s cockpits to speak English. Without the deferential forms of address used in Korean—useful as they may be in other contexts—the crew was able to speak more directly, and as a result, Korean Air went on to achieve one of the best safety records of any airline. The takeaway, according to Gladwell, is that “cultural legacies matter—that they are powerful and pervasive and that they persist.” And, he adds, “when we ignore that fact, planes crash.”

What Gladwell doesn’t address, however, is where these cultural differences come from, and how they become so pervasive in the first place. While it makes sense to think that people from different parts of the world will think about the world differently, we are only beginning to understand how deeply entrenched those differences are—right down to the way our brains themselves function.

Barely two years old, the field of cultural neuroscience is transforming the way scientists think about the brain. “Some of our most basic understandings of the mind and the brain might be really about Western industrialized minds and brains,” says Jon Freeman, a doctoral student in Tufts’ psychology department and the lead author of a chapter on cultural neuroscience for the annual journal Progress in Brain Research. After all, he notes, the vast majority of psychological research has been done in Western industrialized countries. Moreover, recent work suggests there’s “a rich variation in basic mental processes.” Freeman is part of a nucleus of Tufts researchers who are opening the door to determine just how—and how much—culture influences the workings of the brain.

Tufts psychology professor Nalini Ambady puts it this way: cultural neuroscience shows that “there is malleability in the neural structure depending on cultural exposure.” The brain, she says, is a “sponge that absorbs cultural information.” What she and other cultural neuroscientists have discovered is that although the brains of people from different cultures do not exhibit large structural differences, certain neural pathways do become more ingrained from immersion in a particular culture. They’ve also learned that those differences in brain function can influence our emotions, our behavior, and our attitudes toward people from cultures other than our own.

A few years ago, Shinobu Kitayama and colleagues at the University of Michigan conducted a seminal study that highlighted some of the differences between Eastern and Western thinking that Gladwell observed in the Korean Air case. In the so-called framed line test, American and Japanese subjects were shown a simple square frame with a vertical line drawn partway down the middle. The researchers then gave them a new, larger frame and told them to draw a line the same length as the original. But there was a twist. Some people were told to draw a line the same absolute length as the original; others were told to draw one the same relative length compared with the new, larger square.

Across the board, the Americans performed better on the absolute test, while the Japanese excelled on the relative test. The researchers attributed the differences to cultural traits found in previous psychological studies: Americans excel at analyzing specific details, while Asians perceive objects more holistically, taking into account the surrounding context.

Last year, when researchers at the Massachusetts Institute of Technology did brain imaging on subjects as they performed the framed line test, they found differences that went beyond cultural traits. Hooked up to a functional magnetic resonance imaging (fMRI) machine, both Americans and Japanese showed more activity in parts of the brain responsible for increased concentration when they were drawing the line that was more difficult for their cultural group.

To many, such results were heresy. The prevailing view among cognitive neuroscientists was that the brain, like any other organ, evolved to perform distinct activities in distinct ways. Functions such as vision, language, analytical thinking, and emotion were assumed to be neatly compartmentalized in specific areas of everyone’s brain, and it was the neuroscientist’s job to tease apart what did what. Cultural differences were viewed as just so much external noise to be minimized through tightly controlled experiments. And yet the MIT researchers demonstrated that two culturally distinct groups were using different parts of their brain for the same simple task. “As you get to higher levels of complexity, it leaves the door open for all kinds of other differences [in brain function],” Freeman says.

Tufts’ senior vice president and provost, Jamshed Bharucha, a professor in the Department of Psychology, has made it his business to explore some of those higher levels of complexity. He has been investigating what happens in the brain when people of different cultures hear various kinds of music. In preliminary findings yet to be published, he conducted fMRIs of American and Indian students while they listened to American and Indian classical and pop tunes. The results show completely different patterns in the brain scans, with a constellation of different brain regions operating for each of the two groups, even when listening to the same music.

In a paper published in Current Directions in Psychological Science this past December, Ambady and Bharucha use the term “cultural mapping” to describe patterns like the ones revealed in the fMRIs. “When you are exposed to a culture over a lifetime, your brain reorganizes,” contends Bharucha. “The connections between the neurons change, then the brain develops these cultural lenses through which you perceive the world.”

The real-world consequences can be dramatic, as a recent experiment by Nicholas Rule, a Tufts doctoral student in psychology, has demonstrated. Rule showed Japanese and American subjects black-and-white photographs of political candidates—candidates unfamiliar to the subjects—from the both the United States and Japan. He had the subjects rate the photos on four characteristics: dominance, maturity, likeability, and trustworthiness. He combined these into two traits: power and warmth. Then he showed the subjects each photo again and asked if they would vote for that candidate.

The American students overwhelmingly favored the powerful faces, the Japanese students the warm faces. Perhaps not coincidentally, the faces that elicited positive responses in subjects from the same country closely matched the actual election results. In a separate study involving corporate CEOs, Rule’s findings were nearly identical. The business leaders whose faces made a good impression on subjects from their own country turned out to be the ones whose financial success was the greatest.

Another piece of the puzzle fell into place when Rule performed fMRI scans on his subjects. He expected to learn that the Americans were using more analytical areas of the brain and the Japanese more emotional areas. But what he discovered surprised him: both groups were using the same part of the brain—the amygdala. Sometimes called the “lizard brain,” the amygdala, which has been with us since the early days of our evolutionary journey, helps us detect threats, but it has a more general function as well, signifying increased attention to any object in the outside world. In this case, the amygdala was firing for both the American and the Japanese groups when they saw the picture of the leader they preferred.

“It was a little bit of a surprise,” Rule admits. The finding “essentially says that even though we are leading to different outcomes, we are getting there through the same means.” But what accounts for the strong differences in preferences, leading to very different actions in the real world?

Part of the answer might lie in a similar set of studies done by Freeman. He measured the brainwaves of American and Japanese subjects who were shown silhouettes of bodies in postures categorized as “dominant” and “subordinate” (for example, one of someone standing tall with arms crossed and another of someone with head bowed and arms hanging). “It’s been known for a long time that Western cultures encourage dominance and Japanese cultures more subordination in line with collectivist thinking,” Freeman says. “I was looking to see if these East Asians and Westerners perceive dominant and subservient bodies in a different way.”

The results, published in the journal Neuroimage in April 2009, indicate that here, too, people often travel the same route yet end up at destinations miles apart. The silhouettes matching cultural preferences activated another distinct area of the brain in both groups: the limbic reward system. This is the system that releases dopamine into the bloodstream in response to pleasurable stimuli such as drugs, sex, or food. But it’s also engaged whenever the brain wants to tell the body to go after something in the outside world—to pick up a desired cup of coffee or grab a favorite magazine off the rack.

“I found that dominant bodies activated this classic kind of reward circuitry in Westerners and subordinate bodies activated the same reward circuitry for Japanese people,” says Freeman. What’s more, the magnitude of the limbic response corresponded nearly exactly to the subjects’ responses to questionnaire statements about their level of dominance in the world (“I want to control the conversation” and “I am not afraid of providing criticism”). “So if I’m an American, the more dominant I behave in the real world, the more my brain activates the reward regions when thinking about dominance,” Freeman says.

While it’s impossible to rule out genetic differences between races to explain these differences in brain function, evidence increasingly points to culture as the deciding factor. Ambady and Bharucha both caution that further studies are needed—perhaps involving adopted children or immigrants—to determine exactly where genetics ends and culture begins. The most recent studies in the field, however, have already begun to show how malleable the structure of the brain is in response to cultural stimuli.

Joan Chiao, a former graduate student of Ambady at Harvard and now a professor of psychology at Northwestern University (it was she who coined the term cultural neuroscience) administered simple tests about self-judgment to Asian-American students. She discovered that students would make different choices—and show different patterns of brain activity—depending on whether they were “primed” with individualistic or collectivist values before the test.

Some students were given a story to read about a king who chose a warrior based on his fighting abilities, while others were given a story in which the king chose based on family connections. Later, the students were asked to pick which sentences described themselves (“In general, I am humble,” for example, or “When talking to my mother, I am modest”). Those primed by the first story showed increased brain activity when the statements emphasized individuality, while those primed by the second showed increased brain activity when they emphasized group solidarity. The findings, Chiao wrote in a summary, “suggest a neurobiological basis by which people acculturate to novel environments.” In other words, our brainwaves change according to the culture to which we are exposed.

A study conducted by Chiao in October 2009 showed even more strikingly how culture can override genetic imperatives. The study looked at both genetic and cultural factors influencing depression. It found that East Asians disproportionately possess a genetic trait (a short allele on their serotonin transporter gene) that makes them more susceptible than Americans to depression when exposed to stress. And yet Americans have a higher incidence of depression. Chiao concludes that the collectivist culture of East Asians supersedes their genetics in helping to fight off depressive tendencies.

Despite their promise, however, the implications of cultural neuroscience are also rife for misinterpretation. Freeman squirmed a bit when David Brooks, the New York Times political columnist, mentioned his research on dominance and subordination in an article that also discussed research showing that Israelis are more sensitive to certain kinds of pain experienced by others than Arabs are. The blogosphere picked up on the findings, leading the conservative columnist Andrew Sullivan, of The Atlantic, to claim that the research explained why Jews are comparatively liberal.

While his research was spared similar treatment, Freeman worries it could be misconstrued to promote negative stereotypes. “I don’t want people to jump to conclusions that every American is wired to love dominance and every Japanese person is wired to love subordination,” he says. “For Western readers, through the lens of their own culture, there is a lot of value judgment in that.”

Ambady also counsels caution. “The field of cultural neuroscience is very young,” she says, “and we tend to imbue these activations with lots of meaning.” The mainstream media often take the wrong message from cultural neuroscience research, reporting that if differences are found on the level of the brain, they must be somehow hard-wired. But evidence to the contrary abounds. Take the case of Korean Air, where flight crews succeeded in unlearning aspects of their culture that compromised their performance. In some cases—as seen in those Asian-American students who reacted to different kinds of priming—the brain’s cultural programming may turn on a dime. “What cultural neuroscience shows,” Ambady says, is that the brain is “not fixed—it’s malleable.”

At the same time, the young field can also help us understand differences that do exist between cultures—and potentially lead to greater cooperation on international trade, security, and environmental protection. For that to occur, however, we need to overcome big neurological hurdles. In fact, research shows, we may be neurologically conditioned to miss important emotional signals from people outside our own culture. In a study by Chiao, published in the Journal of Cognitive Neuroscience (December 2008), people looked at pictures of faces displaying fear. Our old friend the amygdala showed far more attention when the faces were of people from the subject’s own cultural group than from another group. And a study performed by Ambady’s former postdoctoral fellow Reg Adams (now an assistant professor of psychology at Penn State) showed more activation in a brain area involved with imagining ourselves in another’s shoes—the felicitously named “superior temporal sulcus”—when people viewed pictures of facial expressions worn by members of their own culture.

Both studies imply that prejudice itself has a strong neurological basis. “It shows our preferences for our in-groups and our discrimination against out-group members,” says Ambady. At the same time, if the cultural neuroscientists are right, such reactions can also be unlearned in time. With exposure to other cultures, perhaps, the brain can absorb different ways of perceiving and responding to the world. At the very least, being aware of how deep-seated our perceptions are can help us recognize—maybe even overcome—our natural prejudices.

MICHAEL BLANDING is an award-winning magazine writer whose work has appeared in The Nation, The New Republic, Boston Magazine, and the Boston Globe Magazine.