July 06, 2007
The New York Times slyly abets a lie
Well, a fib, anyhow.
According to Donald G. McNeil Jr., "Everybody's Talking", New York Times, 7/5/2007:
Briefly: Who talks more? Man? Woman?
Conventional wisdom: women use 20,000 words a day, men 7,000. Come cocktail hour, hubby played out. Wife frustrated: 13,000 words to go, no takers.
But wisdom comes from populist 2006 book, "The Female Brain." Data shaky. Skeptics abound.
Today, study published Science magazine: 396 subjects wear tiny microphones. Result: whoops. Women emit 16,125 words per day, men 15,669. Statistically, even-steven.
However, authors admit flaw: all 396 were college students — congenitally loquacious, no jobs, no commutes, no need for aphonic mesmerization by Monday Night Football.
Despite the flaw, says lead author, Matthias R. Mehl, University of Arizona psychologist, "Our paper puts to rest the idea that the female brain evolved to be talkative and the male brain evolved to be reticent."
However, fact slyly not mentioned in Science study: after first printing of "Female Brain," author, Louann Brizendine, began worrying that 20,000 vs. 7,000 figure was just invented by marriage counselors and removed it.
To say that the Science article "slyly" failed to mention this removal is pretty strong language: sly is glossed by MW as "clever in concealing one's aims or ends ... "lacking in straightforwardness and candor", with synonyms furtive and dissembling.
It's true that Dr. Brizendine removed the specific 20,000-vs.-7,000 numbers after being challenged on them ("Word counts", 11/28./2006). However, she in no way retracted the claim that women are more talkative.
Let's be painfully specific.
A passage on p. 14 first said (emphasis added to highlight the changed sentence):
Until eight weeks old, every fetal brain looks female -- female is nature's default gender setting. If you were to watch a female and a male brain developing via time-lapse photography, you would see their circuit diagrams being laid down according to the blueprint drafted by both genes and sex hormones. A huge testosterone surge beginning in the eighth week will turn this unisex brain male by killing off some cells in the communication centers and growing more cells in the sex and aggression centers. If the testosterone surge doesn't happen, the female brain continues to grow unperturbed. The fetal girl's brain cells sprout more connections in the communications centers and areas that process emotion. How does this fetal fork in the road affect us? For one thing, because of her larger communication center, this girl will grow up to be more talkative than her brother. Men use about seven thousand words per day. Women use about twenty thousand. For another, it defines our innate biological destiny, coloring the lens through which each of us views and engages the world.
And in later printings it reads:
Until eight weeks old, every fetal brain looks female -- female is nature's default gender setting. If you were to watch a female and a male brain developing via time-lapse photography, you would see their circuit diagrams being laid down according to the blueprint drafted by both genes and sex hormones. A huge testosterone surge beginning in the eighth week will turn this unisex brain male by killing off some cells in the communication centers and growing more cells in the sex and aggression centers. If the testosterone surge doesn't happen, the female brain continues to grow unperturbed. The fetal girl's brain cells sprout more connections in the communications centers and areas that process emotion. How does this fetal fork in the road affect us? For one thing, because of her larger communication center, this girl will grow up to be more talkative than her brother. In most social contexts, she will use many more forms of communication than he will. For another, it defines our innate biological destiny, coloring the lens through which each of us views and engages the world.
And current printings of the book still say (p. 36)
[W]omen, on average, talk and listen a lot more than men. The numbers vary, but on average girls speak two to three times more words per day than boys.
The end-notes don't offer any source for that estimate. We could, however, appeal to a 2004 meta-analysis (a study of studies, so to speak), C. Leaper and T.E. Smith, "A meta-analytic review of gender variations in children's language use: talkativeness, affiliative speech, and assertive speech", Developmental Psychology 40(6) 993-1027, 2004, which concludes that
On average, girls were slightly more talkative and used more affiliative speech than did boys, whereas boys used more assertive speech than did girls. However, the average effect sizes were either negligible (talkativeness, d=0.11; assertive speech, d=0.11) or small (affiliative speech, d=0.26).
Leaper and Smith surveyed 61 studies for the talkativeness part of their meta-analysis. An "effect size" of 0.11 means that the average difference between girls and boys was about one tenth of a standard deviation -- for more on what this means, see my post "Gabby Guys: the effect size", 9/23/2006.
So I'd say that it's not Matthias Mehl and his co-authors who are being sly.
And it's not only the female-talkativeness claim that still stands in the new version of this passage. The whole word-count business was just one of many shiny factoids decorating the basic structure of what Young and Balaban, reviewing Brizendine's book in Nature, called "Psychoneuroindoctrinology". Some of the falsifiable factoids have been replaced by vaguer versions, but the basic thesis hasn't budged an inch:
If you were to watch a female and a male brain developing via time-lapse photography, you would see their circuit diagrams being laid down according to the blueprint drafted by both genes and sex hormones. A huge testosterone surge beginning in the eighth week will turn this unisex brain male by killing off some cells in the communication centers and growing more cells in the sex and aggression centers. If the testosterone surge doesn't happen, the female brain continues to grow unperturbed. The fetal girl's brain cells sprout more connections in the communications centers and areas that process emotion. [emphasis added]
I discussed the end-notes provided for this passage at tedious length in an earlier post ("The laconic rapist in the womb", 9/4/2006). In particular, I looked in detail at the six references that are cited to support the passage in bold face, and concluded that "none of the references that Brizendine cites in support of this passage provide any empirical support for them at all".
In the later printings (I'm looking at the 12th printing), these references have been updated as follows. Instead of
14: ". . . both genes and sex hormones.": Glickman 2005; Arnold 2004.
14: ". . . the sex and aggression centers.": Sur 2005.
14: ". . . areas that process emotion.": Hill 2006; Herbert 2005; Sun 2005; Witelson 1995; Goldberg 1994.
14: ". . . women use about twenty thousand.": Deacon 1997; Garner 1997; Lewis 1997; Pease 1997; Lakoff 1976; Thorne 1983.
we now have:
14: ". . . both genes and sex hormones.": Arnold 2004.
14: ". . . the sex and aggression centers.": Sur 2005.
14: ". . . areas that process emotion.": See Chapter 6, "Emotions."
14: ". . . communication than he will.": Tannen 1990.
So the irrelevant Glickman 2005 is gone; the irrelevant review in Sur 2005 remain as the only support for the claim that fetal testosterone kills cells in "communication centers" and grows cells in the "sex and agression centers"; support for the claim about fetal girls sprouting more connections in the communication centers and the centers that process emotion has been deferred to Chapter 6; and Tannen 1990 is cited in support of the "many more forms of communication" claim; and
There's a lot to say about Brizendine's Chapter 6 -- but there's nothing in the text about sex differences in fetal brain development, and I don't see anything in the end-notes that seems relevant either.
I'll take up the Tannen reference and the business about "more forms of communication" another time. As for the rest of it, there's still no scientific support whatsoever offered for the morality play about the fetal origins of male sex and aggression vs. female communication and emotion.
But this morality play is the meat of the matter. The word counts and other shiny factoids are just the sauce.
Of course, that sauce is still being ladled out. Check out the publisher's blurb at Powell's Books for the paperback edition of The Female Brain, due to be released on August 7, 2007:
Louann Brizendine, M.D. is a pioneering neuropsychiatrist who brings together the latest findings to show how the unique structure of the female brain determines how women think, what they value, how they communicate, and who they'll love. Brizendine reveals the neurological explanations behind why
- A woman uses about 20,000 words per day while a man uses about 7,000
- A woman remembers fights that a man insists never happened
- A teen girl is so obsessed with her looks and talking on the phone
- Thoughts about sex enter a woman's brain once every couple of days but enter a man's brain about once every minute
- A woman knows what people are feeling, while a man can't spot an emotion unless somebody cries or threatens bodily harm
- A woman over 50 is more likely to initiate divorce than a man
Women will come away from this book knowing that they have a lean, mean communicating machine. Men will develop a serious case of brain envy.
The same blurb is used on the publisher's web site to promote the e-book version, also due out August 7 -- I snarfed this screen shot a few minutes ago:
