Are there sex differences in the development of prefrontal function during early childhood?

Research has demonstrated the possibility of minor sex differences in executive function (EF) development of young children; however, this may be limited to the measurements used in previous studies (questionnaires and cognitive tasks), which tend to be less sensitive to the detection of sex differences. The present study uses brain measures to examine the effect of sex on EF development. In this study, preschool children were given an EF task, and patterns of activation in the lateral prefrontal regions were measured by a functional near-infrared spectroscopy. In Study 1, there were no behavioral differences between girls and boys, though girls showed stronger prefrontal activation than boys. Study 2 was conducted as an attempt to replicate the results, and some of the results were inconsistent with the results in Study 1. Results suggest that sex differences in EF tasks are small, although such differences may exist irrespective of methodology.