By ROBIN MARANTZ HENIG
Jerome Kagan’s “Aha!” moment came with Baby 19. It was 1989, and Kagan, a professor of psychology at Harvard, had just begun a major longitudinal study of temperament and its effects. Temperament is a complex, multilayered thing, and for the sake of clarity, Kagan was tracking it along a single dimension: whether babies were easily upset when exposed to new things. He chose this characteristic both because it could be measured and because it seemed to explain much of normal human variation. He suspected, extrapolating from a study he had just completed on toddlers, that the most edgy infants were more likely to grow up to be inhibited, shy and anxious. Eager to take a peek at the early results, he grabbed the videotapes of the first babies in the study, looking for the irritable behavior he would later call high-reactive.
No high-reactors among the first 18. They gazed calmly at things that were unfamiliar. But the 19th baby was different. She was distressed by novelty — new sounds, new voices, new toys, new smells — and showed it by flailing her legs, arching her back and crying. Here was what Kagan was looking for but was not sure he would find: a baby who essentially fell apart when exposed to anything new.
Baby 19 grew up true to her temperament. This past summer, Kagan showed me a video of her from 2004, when she was 15. We sat in a screening room in Harvard’s William James Hall — a building named, coincidentally, for the 19th-century psychologist who described his own struggles with anxiety as “a horrible dread at the pit of my stomach ... a sense of the insecurity of life.” Kagan is elfin and spry, balding and bespectacled. He neither looks nor acts his age, which is 80. He is one of the most influential developmental psychologists of the 20th century.
On the monitor, Baby 19 is a plain-looking teenager, hiding behind her long, dark hair. The interview, the same one given to all 15-year-olds in the longitudinal study, begins with questions about school. She has very few extracurricular activities, she says in a small voice, but she does like writing and playing the violin. She fidgets almost constantly as she speaks, twirling her hair, touching her ear, jiggling her knee. “This is the overflow of her high-reactive nature,” Kagan told me, standing near the monitor so he could fast-forward to the good parts.
Here was a good part: The interviewer asks Baby 19 what she worries about.
“I don’t know,” Baby 19 says after a long pause, twirling her hair faster, touching her face, her knee. She smiles a little, shrugs. Another pause. And then the list of troubles spills out: “When I don’t quite know what to do and it’s really frustrating and I feel really uncomfortable, especially if other people around me know what they’re doing. I’m always thinking, Should I go here? Should I go there? Am I in someone’s way? ... I worry about things like getting projects done... I think, Will I get it done? How am I going to do it? ... If I’m going to be in a big crowd, it makes me nervous about what I’m going to do and say and what other people are going to do and say.” Baby 19 is wringing her hands now. “How I’m going to deal with the world when I’m grown. Or if I’m going to sort of do anything that really means anything.”
Her voice trails off. She wants to make a difference, she says, and worries about whether she will. “I can’t stop thinking about that.”
Watching this video again makes Kagan fairly vibrate with the thrill of rediscovery: here on camera is the young girl who, as an infant, first embodied for him what it meant to be wired to worry. He went on to find many more such children, and would watch a big chunk of them run into trouble with anxiety or other problems as they grew up.
The tenuousness of modern life can make anyone feel overwrought. And in societal moments like the one we are in — thousands losing jobs and homes, our futures threatened by everything from diminishing retirement funds to global warming — it often feels as if ours is the Age of Anxiety. But some people, no matter how robust their stock portfolios or how healthy their children, are always mentally preparing for doom. They are just born worriers, their brains forever anticipating the dropping of some dreaded other shoe. For the past 20 years, Kagan and his colleagues have been following hundreds of such people, beginning in infancy, to see what happens to those who start out primed to fret. Now that these infants are young adults, the studies are yielding new information about the anxious brain.
These psychologists have put the assumptions about innate temperament on firmer footing, and they have also demonstrated that some of us, like Baby 19, are born anxious — or, more accurately, born predisposed to be anxious. Four significant long-term longitudinal studies are now under way: two at Harvard that Kagan initiated, two more at the University of Maryland under the direction of Nathan Fox, a former graduate student of Kagan’s. With slight variations, they all have reached similar conclusions: that babies differ according to inborn temperament; that 15 to 20 percent of them will react strongly to novel people or situations; and that strongly reactive babies are more likely to grow up to be anxious.