And now...the exciting conclusion of the dialogue between New York Times science writer Robin Marantz Henig and myself, about some word choices in Henig's excellent piece about the science of anxiety in Sunday's Times Magazine.
We'll begin with Henig's last published answer:
RMH: "Worry comes early" is a better phrase, but guess what -- that's not really accurate, either. Kagan is not saying that these high-reactive infants are worrying. What he's saying is that a temperament that predisposes a person to worrying (and also to behavioral inhibition, shyness, a tendency to be inner-directed, and a higher risk of clinical anxiety disorder) relates to a hyper-reactive amygdala, which in an infant creates the specific motor activity he measured--kicking, arching the back, fussing, crying when exposed to novel stimuli. Later in life, this hyper-reactive amygdala leads to different outward signs: social withdrawal and a kind of freezing behavior in early childhood, interior fretfulness and sometimes clinical anxiety disorders in adolescence and adulthood. These babies aren't worrying early. They are predisposed early to worrying.
I'm not at home at the moment, and the New York Times fact-checker still hasn't returned most of my Kagan books anyway, but I'm pretty sure he would not object to the statement that these traits ARE present from birth. They just look different at different ages. Even at one or two days of age you can see a high-reactive temperament, which in the neonatal period is exhibited by the rate at which the infant sucks on a nipple. There was an experiment that involved feeding newborns sugar water with different concentrations of sweetness. Since I don't have the book at hand, I'm afraid I can't cite the specifics, but I do remember that some babies, when the concentration changed, reacted with a much greater increase in their speed of sucking. I'm pretty sure (I need to get home next week to check this out) that the two-day-old infants who sucked fastest in response to novelty -- the neonatal correlate of high reactivity -- were more likely to grow up to look like the behaviorally inhibited and anxiety-prone children in Kagan's study. I see this as evidence that temperament probably IS present at birth, at least to some degree.
DS: So now the task, as I see it, is to come up with language that is consistent with all these true statements of yours:
- "temperament probably IS present at birth, at least to some degree"
- "it's a stretch to assume that traits that are measurable at four months were present at birth"
- "environmental influences on gene expression exist not only from the moment of birth, but before."
- "two organisms can be distinctly different even when they have identical DNA."
I suggest that the answer is to use language that emphasizes the dynamic process, and to carefully avoid words that suggest built-in features. What we want to convey is that nature and nurture are never distinct from one another. Each person's genes strongly influence the process from conception, and so does each person's experience and surroundings. I suggest that words like "wired," "innate," "inborn," "natural-born," "gifted," "pre-set," and, of course, "gene-based" suggest the old built-in, fixed-trait paradigm. What we want is words and phrases that suggest process: "formation," "influence," "dynamic," "interact," "affect," "shaping," "path toward," "inklings of," "direction," etc.
It's also not helpful to assign a "heritability" percentage as some--not you--do because the process in every individual is so dynamic. Heritability speaks to group averages, not to individual experience or potential. We can't say *how much* is determined by one side or the other; we can only try to learn more about all the dynamic elements involved and how they influence one another. And we can try to articulate when and how certain traits become more concrete and less plastic while being very careful not to overstate either their concreteness or their plasticity. You do such an amazing job in the piece, and in this forum, of emphasizing the relative plasticity of temperament throughout one's life. I think it's a terrible shame to be less precise when talking about the process in-utero and in infancy.
Am I able to convince you to avoid those old-paradigm words, or do you still think they have a vitality?
RMH: I like your suggestion to think about replacing static, old-school words like "inborn" or "innate" with the words you prefer, like "dynamic" and "interact" and "inklings." That's all fine. The terminology we use helps shape our view of the world, and this is no more true than in the case of science -- and science journalists are in a good position to choose the more felicitous wording and, by using it over and over again, turning it into common everyday parlance. But use those words in a sentence, David -- do they really convey exactly what you want them to convey? Or are they currently so rarely used that they will only serve to muddy the waters?
Let's choose a sentence in my article where I use one of the bad-guy words, and try reworking it to include one of yours. I looked for one quickly in my copy of the Magazine, and the truth is I had trouble finding one--I'm only finding terms like "anxiety-prone" or "high-risk" (once we get past the "wired to worry" nut graf you've already chastised me for). Please help me find an offending sentence, and let's see if there's a way to use one of your preferred words in a way that still makes sense.
DS: Ok, well obviously it's never going to be as simple as swapping one word for another. But let's take this sentence:
"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."
Is there a way to rewrite this sentence to suggest, instead, that these psychologists have demonstrated that temperament is composed of different components, some of which seem to develop in the first few months of infancy and some probably even before birth? I grant you that it might be difficult to articulate that in a snappy sentence. (I'm not going to take an hour right now to do so.) But if you agree that it's an important goal to convey it as a developmental process rather than a static entity, I hope you'll also agree that finding the correct, clever phrasing won't be impossible.
RMH: I agree that it's never impossible to find correct, clever phrasing--and I would add that one essential component of such phrasing is also that it be accurate. But I disagree on the necessity to rewrite this particular sentence. What about "predisposed to be anxious" fails to convey the developmental, dynamic process you talk about? The sentence does still use the word "innate," which I know is a problem for you, and maybe that one word CAN be swapped--or even eliminated. You don't object to the concept of a temperament, do you, without any modifier?
I also am confused about why you seem so eager to emphasize that some traits develop before birth. Having not read your book, I'm at a disadvantage, but it sounds like you're making your job even harder. I guess your point is that even traits that are seen from the moment of birth are not necessarily inherent in the DNA, that even the intrauterine environment helps determine gene expression. In my experience, it's hard enough getting across that concept when the environment is something we all can see. To get our conversation back to word choice--do words even exist that convey the distinction between pre-birth and post-birth environmental influences?
DS: At the risk of sounding like a broken record, I think that all three phrases here--"innate temperament," "born anxious," and even "born predisposed to be anxious"--endorse a certain static viewpoint. You've demonstrated pretty thoroughly in our discussion that that was not your intent, but I think that's how most readers will read these phrases. "Predisposed" will sound to many, if not most, readers like a genetic predisposition.
It's not that I'm especially eager to prove certain traits developing before birth, but that I'm so eager to demonstrate how life is a developmental process from the day of conception onward. Part of understanding the new nature-nurture dynamic is realizing that even a lot of the nurture stuff isn't necessarily in our direct control. (Ironically, it turns out that we may be able to influence some of the genetic/nature stuff through epigenetics -- but that's a discussion for another time.)
To address your last question, we writers definitely have some work to do to come up with words and phrases that capture this new paradigm. Inevitably, these new words and phrases won't have the same sizzle as innate, inborn, hard-wired and so on. But hopefully we'll come up with some new stuff that is clever and accurate.
I want to thank you, Robin, for hashing this out, and for opening your piece up to brutal, word-by-word scrutiny. I've enjoyed our dialogue. I hope you have too. Please come back in March and dissect a section of my book.
RMH: Wow, an offer of a rematch in March, with YOUR work on the slab -- you're a brave man, David. Meanwhile, thanks for the chance to engage in this interesting to-ing and fro-ing.
DS: Not brave, just fair. Thanks.
(Part 1 is also available)
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David Shenk is a writer on genetics, talent and intelligence. He is the author of Data Smog, The Forgetting, and most recently, The Genius In All of Us.