He's cool. Cold. An iceberg. We all know people who don't need people.
Whether they flit from one relationship to another, remain mysteriously aloof, or eschew love for a higher purpose, these folks seem immune to the pains pangs and joys of love.
David Chun wants to know how their brains work.
Chun is a graduate student working in the Adult Attachment Lab at UC Davis. The lab is headed by Phil Shaver, who, building on the pioneering work of John Bowlby and Mary Ainsworth, is one of the preeminent psychologists studying attachment. ("Attachment in Adulthood," a book by Shaver and Mario Mikulincer, is in press.)
While we intuitively feel that, somehow, our mothers reach out from our childhoods to influence adult behavior, Shaver and his students are charting exactly how that happens.
Chun is one of a new generation of psychologists who are using the tools of neuroscience to discover how mothering shapes the way the brain works. They’re finding just how deeply engrained is the way we approach relationships: How we love -- or why we can't -- seems to be etched into the circuits of the brain.
His work is exciting and important, because he's using analytical, quantitative tools to examine what so far have only been theories of psychology.
The question Chun is trying to answer is, "Are there differences in brain functioning between individuals with different attachment styles?" This research question is a lifelong adventure; Chun has started by looking at the brains of people who are high in what psychologists call avoidance.
The theory of attachment proposed by Bowlby and Ainsworth, and further developed by Shaver and others, identifies four different attachment styles -- the way we tend to approach close relationships with others. These styles were based on observations of young children with their mothers; Chun is one of many researchers elucidating how we bring what we learned about getting what we needed from Mommy to our lovers and mates.
Chun is looking at "avoidant" people, those who try to protect themselves from rejection by shutting the door on intimacy. Their motto is, "You can't hurt me if you can't get near me."
Researchers have discovered something fascinating: This tends to work.
We may suspect that these social icicles are seething volcanoes of emotion inside. In Casablanca, when Bogie watches Ingrid Bergmann walk out of his life forever and then heads back to his bar for a nightcap, we assume he's dying inside.
But when Chun looks at the brains of these icebergs, they seem to be doing fine, thank you very much, as long as their defenses go unchallenged.
To find the avoidant types he wants to put under the fMRI scanner, Chun gives them a standard questionnaire designed to uncover attachment styles. Avoidant people tend to agree with statements like, "I prefer not to show a partner how I feel deep down." Anxious people, on the other hand, agree with statements like, "I worry that romantic partners won’t care about me as much as I care about them."
Chun built his research on two concepts. First, it's really hard not to think about something when someone tells you not to. It's the classic, "Don't think about a white bear" conundrum. The more you try not to think about that bear, the more it lumbers through your thoughts.
Second, you can reliably tell just how anxious someone is by measuring the conductivity of her skin. The more it conducts electricity, that is, the higher the galvanic response, the more she's fretting.
Another of Shaver’s students, Chris Fraley, did some studies showing that avoidant defenses work pretty well. Fraley, now a faculty member at the University of Illinois, hooked people up to sensors that measured their skin conductance. He asked them to think about a painful breakup with a boyfriend or girlfriend, and measured their anxiety. Then, he told them not to think about the breakup.
People who'd scored as anxious on the questionnaire couldn't stop thinking about their exes; they got even more anxious. But the avoidant subjects chilled. They seemed to be able to control their feelings.
Chun is comparing the brain activity of avoidant women with the brain activity of those who are very anxious in relationships, always worrying that friends and lovers won’t be there when they need them.
As a test subject lies under the scanner, Chun asks her to think about a boyfriend who broke up with her. Next, Chun gives her a Stroop test. This research tool, presented on a computer screen, cycles through emotionally neutral words like "book" or "table." Words are presented in different colors, and the subject is asked to name the color of the word, instead of reading the word. Occasionally, the Stroop test slips in a loaded word like "abandoned," words that reinforce the sad memory of a breakup.
In the scanner, Chun sees the areas of the brain that process these emotions glow as more blood travels to them.
When anxious people see the negative words, they're a bit slower to name the color, because they can’t help thinking about the meaning of the word. But those sad words don’t slow down the avoidant people at all.
Next, he gives the test subject a "cognitive load," a mental task designed to interfere with emotional defenses. In Chun's study, they're asked to remember a seven-digit number while seeing the words and trying to name their colors.
What he hopes to see is that, as the brains of avoidant individuals struggle to remember the number, their defenses will break down, and they'll be slower to name the colors of the emotionally loaded words in the Stroop test. (This has already been shown outside the scanner in lab studies by Chun’s colleagues.)
As he watches this process under fMRI, he may be able to see exactly where in the brain these avoidant people push those hurtful thoughts -- and how those areas of the brain come to life when the defenses are interrupted.
Previous fMRI studies have shown increased activity in the anterior cingulate cortex, a part of the brain scientists believe is used for monitoring and responding to conflict. When the ACC detects conflict, they hypothesize, it sends a message to the prefrontal cortex, or PFC, the part of the brain that regulates conflict and inhibition. You could say that the ACC is the part of the brain that senses the conflict, while the prefrontal cortex takes a controlled approach to fixing the problem.
In other words, avoidant people may have learned to apply the intellect directly to a hurt without feeling it.
Chun's hypothesis is that the avoidant loners will show less activity in the ACC and more in the prefrontal cortex when they encounter the loaded words.
In other words, avoidant people have learned to apply the intellect directly to a hurt without feeling it.
"We think that maybe these avoidant people have a strong need to be in control," Chun says. "They are good at emotion regulation," the process by which we calm ourselves down when we need to. "So, perhaps they do recruit more activity in the prefrontal cortex."
Chun is betting that, under the high cognitive load, these avoidant types will show increased activity in the feeling ACC, because the thinking prefrontal cortex is busy remembering the number and can’t take charge.
He thinks that other emotional areas of the brain, including the amygdala, the hypothalamus, and the hippocampus will be more active when stressful words appear under the cognitive load. He's not sure whether this will include the hypothalamus, the seat of oxytocin, but he says he wouldn't be surprised.
