Think Again: Men and Women Share Cognitive Skills

Research debunks myths about cognitive difference.

What the Research Shows

Are boys better at math? Are girls better at language? If fewer women than men work as scientists and engineers, is that aptitude or culture? Psychologists have gathered solid evidence that boys and girls or men and women differ in very few significant ways -- differences that would matter in school or at work -- in how, and how well, they think.

At the University of Wisconsin, Janet Shibley Hyde has compiled meta-analytical studies on this topic for more than 10 years. By using this approach, which aggregates research findings from many studies, Hyde has boiled down hundreds of inquiries into one simple conclusion: The sexes are more the same than they are different.

In a 2005 report, Hyde compiled meta-analyses on sex differences not only in cognition but also communication style, social or personality variables, motor behaviors and moral reasoning. In half the studies, sex differences were small; in another third they were almost non-existent. Thus, 78 percent of gender differences are small or close to zero. What's more, most of the analyses addressed differences that were presumed to be reliable, as in math or verbal ability.

At the end of 2005, Harvard University's Elizabeth Spelke reviewed 111 studies and papers and found that most suggest that men's and women's abilities for math and science have a genetic basis in cognitive systems that emerge in early childhood but give men and women on the whole equal aptitude for math and science. In fact, boy and girl infants were found to perform equally well as young as six months on tasks such as addition and subtraction (babies can do this, but not with pencil and paper!).

The evidence has piled up for years. In 1990, Hyde and her colleagues published a groundbreaking meta-analysis of 100 studies of math performance. Synthesizing data collected on more than three million participants between 1967 and 1987, researchers found no large, overall differences between boys and girls in math performance. Girls were slightly better at computation in elementary and middle school; in high school only, boys showed a slight edge in problem solving, perhaps because they took more science, which stresses problem solving. Boys and girls understood math concepts equally well and any gender differences narrowed over the years, belying the notion of a fixed or biological differentiating factor.

As for verbal ability, in 1988, Hyde and two colleagues reported that data from 165 studies revealed a female superiority so slight as to be meaningless, despite previous assertions that "girls are better verbally." What's more, the authors found no evidence of substantial gender differences in any component of verbal processing. There were even no changes with age.

What the Research Means

The research shows not that males and females are - cognitively speaking -- separate but equal, but rather suggests that social and cultural factors influence perceived or actual performance differences. For example, in 1990, Hyde et al. concluded that there is little support for saying boys are better at math, instead revealing complex patterns in math performance that defy easy generalization. The researchers said that to explain why fewer women take college-level math courses and work in math-related occupations, "We must look to other factors, such as internalized belief systems about mathematics, external factors such as sex discrimination in education and in employment, and the mathematics curriculum at the precollege level."

Where the sexes have differed on tests, researchers believe social context plays a role. Spelke believes that later-developing differences in career choices are due not to differing abilities but rather cultural factors, such as subtle but pervasive gender expectations that really kick in during high school and college.

In a 1999 study, Steven Spencer and colleagues reported that merely telling women that a math test usually shows gender differences hurt their performance. This phenomenon of "stereotype threat" occurs when people believe they will be evaluated based on societal stereotypes about their particular group. In the study, the researchers gave a math test to men and women after telling half the women that the test had shown gender differences, and telling the rest that it found none. Women who expected gender differences did significantly worse than men. Those who were told there was no gender disparity performed equally to men. What's more, the experiment was conducted with women who were top performers in math.

Because "stereotype threat" affected women even when the researchers said the test showed no gender differences - still flagging the possibility -- Spencer et al. believe that people may be sensitized even when a stereotype is mentioned in a benign context.

How We Use the Research

If males and females are truly understood to be very much the same, things might change in schools, colleges and universities, industry and the workplace in general. As Hyde and her colleagues noted in 1990, "Where gender differences do exist, they are in critical areas. Problem solving is critical for success in many mathematics-related fields, such as engineering and physics." They believe that well before high school, children should be taught essential problem-solving skills in conjunction with computation. They also refer to boys having more access to problem-solving experiences outside math class. The researchers also point to the quantitative portion of the Scholastic Aptitude Test (SAT), which may tap problem-solving skills that favor boys; resulting scores are used in college admissions and scholarship decisions. Hyde is concerned about the costs of scientifically unsound gender stereotyping to individuals and to society as a whole.

Sources & Further Reading

Hyde, J. S., & Linn, M. C. (1988). Gender differences in verbal ability: A meta- analysis. Psychological Bulletin, 104, 53-69.

Hyde, J.S., Fennema, E., & Lamon, S. (1990). Gender differences in mathematics performance: A meta-analysis. Psychological Bulletin, 107, 139-155.

Hyde, J.S. (2005) The gender similarities hypothesis. American Psychologist, 60(6), 581-592.

Spelke, Elizabeth S. (2005). Sex differences in intrinsic aptitude for mathematics and science?: A critical review. American Psychologist, 60(9), 950-958.

Spencer, S.J., Steele, C.M., & Quinn, D.M. (1999) Stereotype threat and women's math performance. Journal of Experimental Social Psychology, 35, 4-28.

American Psychological Association, January 18, 2006