Jerome Kagans 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 Kagan was tracking it along a single dimension: whether babies were easily upset when exposed to new things.
It seemed to explain much of normal human variation. Extrapolating from a study he had completed on toddlers,he suspected that the most edgy infants were more likely to grow up to be inhibited,shy and anxious.
He found no high-reactors among the first 18. They gazed calmly at things 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,one of the most influential developmental psychologists of the 20th Century,was looking for: a baby who essentially fell apart when exposed to anything new.
Baby 19 grew up true to her temperament. A video of her from 2004,when she was 15,showed a plain-looking teenager,hiding behind her long,dark hair. The interview,given to all 15-year-olds in the longitudinal study,began with questions about school. She had very few extracurricular activities,she said,but she does like writing and playing the violin. She fidgeted constantly,twirling her hair,touching her ear,jiggling her knee.
Then interviewer asked what she worried about. I dont know, Baby 19 said after a long pause,twirling her hair faster,touching her face,her knee. Then the list of troubles spilled out: When I dont quite know what to do and its really frustrating. I worry about things like getting projects done… I think,Will I get it done? How am I going to do it? … If Im going to be in a big crowd,that even makes me nervous. How Im going to deal with the world when Im grown?
Here on camera was the young girl who,as an infant,first embodied what it meant to be wired to worry. And Kagan went on to find many more such children,and watched a big chunk of them run into trouble with anxiety or other problems as they grew up.
AGE OF ANXIETY
The tenuousness of modern life can make anyone feel overwrought. And now,with thousands losing jobs and homes,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 born worriers.
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.
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 underway: two at Harvard that Kagan initiated,two more at the University of Maryland under the direction of Nathan Fox,a former graduate student of Kagans.
With slight variations,they all have reached similar conclusions: that babies differ according to inborn temperament; that 15 to 20 per cent of them will react strongly to novel people or situations; and that strongly reactive babies are more likely to grow up to be anxious.
They have also shown that while temperament persists,the behaviour associated with it doesnt always. One person might describe a hyperaroused brain in a negative way,as feeling anxious or tense,while another might enjoy the sensation and use a positive word like alert. Some repress the bad feelings and act normally; others withdraw.
WHAT IS ANXIETY
Anxiety is not fear,exactly,because fear is focused on something right in front of you,a real and objective danger. It is instead a kind of fear gone wild,a generalised sense of dread about something out there that seems menacing but that in truth is not menacing,and may not even be out there. If youre anxious,you find it difficult to talk yourself out of this foreboding; you become trapped in an endless loop of what-ifs.
But when the fear starts to interfere with functioning,worrying turns into a clinical anxiety disorder,of which there are several forms: panic,social anxiety,phobia,obsessive-compulsive,post-traumatic stress and a catch-all called generalised anxiety disorder. Taken together,they make anxiety the most common mental illness.
In the brain,worry can often be traced to overreactivity in the amygdala,a small site in the middle of the brain that,among its many other functions,responds to novelty and threat. When the amygdala works as it should,it orchestrates a physiological response to changes in the environment. That response includes heightened memory for emotional experiences and the familiar chest pounding of fight or flight. But in people born with a particular brain circuitry,the kind seen in Kagans high-reactive study subjects,the amygdala is hyperreactive,prickly as a haywire motion-detector light that turns on when nothings moving but the rain.
COPING WITH ANXIETY
Having all the earmarks of anxiety in the brain does not always translate into a subjective experience of anxiety. Two people can experience the same level of anxiety,but one who has work interesting enough to distract might do fine.
But even so,people with a nervous temperament dont usually get off easily,Kagan and his colleagues have found. There exists a kind of sub-rosa anxiety,a secret stash of worries that continue to plague people no matter how well they function outwardly.
Functioning well depends on adaptation and adapting might have something to do with intelligence,says Steven Pinker,a psychologist at Harvard and author of The Blank Slate: The Modern Denial of Human Nature. He says people with higher intelligence are better at overcoming their anxious temperament and more likely to see their own worry list as a problem to be solved.
At least one study lends support to Pinkers impression. In a 2004 article called Can Worriers Be Winners? two British scientists found that among a group of managers,those who reported themselves as scoring high on anxiety traits,turned out to be better employees,but only if their worrying was accompanied by high cognitive ability.
In the modern world,the anxious temperament does offer certain benefits: caution,introspection,the capacity to work alone. Kagan has observed that the high-reactives in his sample tend to avoid the traditional hazards of adolescence. Because they are more restrained than their wilder peers,he says,high-reactive kids are less likely to experiment with drugs,to get pregnant or to drive recklessly.
People with a high-reactive temperament as long as it doesnt show itself as a clinical disorder are generally conscientious and almost obsessively well-prepared. Worriers are likely to be the most thorough workers and the most attentive friends. Someone who worries about being late will plan to get to places early. Test-taking anxiety can lead to better studying. Kagan said he would bet that in space missions,the brave astronauts were low-reactive as infants,and the mission-control people down on the ground,doing the detail work that keeps the craft aloft,were high-reactive.
An anxious temperament might serve a more exalted function too. Our culture has this illusion that anxiety is toxic, Kagan said. But without inner-directed people who prefer solitude,where would we get the writers and artists and scientists and computer programmers who make society hum?