Last January, Harvard University President Lawrence Summers, PhD, suggested that men outperform women in high-level science and mathematics due to genetics, not life experience. However, an analysis by Harvard University psychology professor Elizabeth Spelke, PhD, in the American Psychologist (Vol. 60, No. 1) counters that suggestion. Her review finds that boys and girls share the same biologically-based cognitive capacities from which mathematical and scientific reasoning develop.

"There is an asymmetry in the way Summers' evidence of sex differences is considered," says Spelke. Many investigators focus on a niche of studies that show small cognitive differences between men and women on a few tasks while ignoring numerous studies that have found that male and female infants and children have equal aptitude for math and science, she says.

As Spelke reviewed 111 studies and review papers, she found that the majority of studies suggested that both men's and women's mathematical and scientific abilities have a genetic basis in cognitive systems that emerge in early childhood. When researchers compare male and female infants' and children's performances, they find that they perform equally well. For instance, 6-month-old boys and girls equally perform simple additions and subtractions and compare one small set to another.

Later-developing differences in career choices, such as fewer women entering math and science departments at the graduate level, likely are due to cultural factors, Spelke says. To better evaluate men's and women's mathematical and scientific abilities, researchers should consider how the social forces of high school and college classrooms influence students' interests and academic pursuits, and how subtle but pervasive social expectations influence perceptions and evaluations of talented young men and women, she suggests.