Adolescent males and females appear to use somewhat different brain areas when processing language tasks, according to a study appearing this week in Neuropsychologia. The finding could lend support to different educational approaches for boys and girls.
It's well established that girls score higher than boys in most tests involving language, such as verbal fluency and word memory. So cognitive scientists Douglas Burman and James Booth at Northwestern University in Evanston, Illinois, sought to see if there are differences in brain activity that underlie these sex differences.
The researchers administered several word tests to about 50 children aged 9 to 15, half of them girls. Paired words were either flashed on a screen or spoken, and subjects had to judge whether they rhymed, for example. Subjects' brain activity in response to each task was monitored by functional magnetic resonance imaging, which measures blood flow to various parts of the brain. The researchers found that girls showed significantly greater activation of the language areas of the brain than did boys. The boys showed greater activation of the specific sensory brain areas--visual or auditory--required by the task.
The researchers conclude that girls rely more on universal language-processing machinery that operates regardless of how they receive the information, whereas boys process information depending on the sensory mode. These differences don't necessarily persist into adulthood, according to Burman's team. It might just reflect the fact that males take longer to mature than females. But the findings could have implications for education--suggesting, for example, that separating the sexes in middle school may not be a bad idea, Burman says.
Psychologist Ruben Gur of the University of Pennsylvania calls the study "an important contribution." There are a lot of studies on sex differences in cognition and a lot of studies showing sex differences in the brain, he says. "But it's very rare" to have a study in which the two types of findings are correlated. Brain imager Richard Haier of the University of California, Irvine, adds that the conclusions "fit nicely" with findings he has reported on sex differences in the brain areas used in intelligence tests. "This paper is part of a growing awareness that not all brains work the same way," he says.