In the uproar over Lawrence Summers' remarks on the comparative abilities of men and women, one element was conspicuously absent: Evidence.
An AP article published today under the headline, "Summers' Remarks Supported by Some Experts" notes that Summers' view, while far from a proven fact, is supported by (at least some) evidence and by (at least some) experts in psychology and medicine.
Anyone with an opinion about Summers' comments should read this article. It doesn't answer all the questions. For instance, it doesn't settle whether Summers was speaking out of turn for a university president schooled in economics, regardless of supporting evidence.
But the best opinions are educated ones. More from the article below.
In sum, the article argues:
Harvard University president Lawrence Summers has suffered acrimonious condemnation, and may have jeopardized his job, for suggesting that the underrepresentation of women in engineering and some scientific fields may be due in part to inherent differences in the intellectual abilities of the sexes. But Summers could be right.
Some scholars who are in the know about the differences between mens' and womens' brains believe his remarks have merit.
Two academics quoted in the article discuss the issue:
"Among people who do the research, it's not so controversial. There are lots and lots of studies that show that mens' and womens' brains are different," says Richard J. Haier, a professor of psychology in the pediatrics department of the University of California Los Angeles medical school.
...
"I think it's an outrage that certain questions that real, important questions can't be raised in an academic atmosphere, that research that's well-known can't be presented without some sort of hysterical response," says Linda S. Gottfredson, a psychologist at the University of Delaware.
The article summarizes recent research on gender-based difference in brain structure as follows:
In recent years, scientists have found that male and female brains are wired differently from one another, due to the role of testosterone and other male hormones during gestation. Brains growing under the influence of male hormones are slightly larger and have denser concentrations of neurons in some regions.
Male brains also contain a greater proportion of gray matter, the part of the brain responsible for computation, while women have relatively more white matter, which specializes in making connections between brain cells.
These differences could support the explanation Summers suggested:
Brain-imaging studies suggest that both sexes exploit these differences to their benefit. UCLA researchers have done brain scans of men and women who scored in the top 1 percent on the math section of the SAT. As they worked on math problems, the men relied heavily on the grey matter in the brain's parietal and cerebral cortices. Women showed greater activity in areas dominated by the well-connected white matter.
"Maybe they're doing the math using the white matter," Haier says. "It's not completely unreasonable."
Other evidence discussed in the article:
Intelligence tests have found that men, on average, perform better on spatial tasks that require mentally rotating or otherwise manipulating objects. Men also do better on tests of mathematical reasoning. Women tend to do better than men on tasks requiring verbal memory and distinguishing whether objects are similar or different. The relative strengths even out, so on average the sexes are of equal intelligence.
Some studies also have suggested that the IQ distribution is more spread out among men. If that is true, then there are proportionately more men at the extremely brilliant end of the IQ scale and the dull end as well.
The article cites the competing views of Joshua Aronson, a professor of applied psychology at New York University:
"If I had to guess, the real reason for the lack of women in the upper strata is that there's a comfort zone when you walk into a classroom and see a certain number of people like you... If there is a biological difference, then it's one that's awfully easy to overcome."
The conclusion Professor Aronson draws, however, seems to be less about the correctness of Summers' view and more about the potential it could be misinterpreted or misused:
"When people hear 'biology' they think there's nothing you can do about it.... It's in that context that Summers' remarks are not helpful."
I don't mean to suggest that the views expressed in support of Summers' statements should end the inquiry. There remain questions about the propriety of Summers, an economist occupying a position of great public visibility at a prestigious academic institution, raising such a controversial issue without marshalling the evidence in advance. Nevertheless, the debate about Summers' statements should proceed with all available information.
