Prepubescent children show the adult relationship between dermatoglyphic asymmetry and performance on sexually dimorphic tasks

The dermatoglyphic pattern of dermal ridges that constitutes the human fing erprint is complete by the 16th foetal week and its development is thought to be influenced by prenatal hormones. Finger ridge count (FRC) is asymmetr ical with the majority having more ridges on the finger tips of the right h and (R >) while the minority have more on the left (L >). In adults, the R > condition has been associated with male-typical, and the L > condition wi th female-typical, performance on sexually dimorphic tasks. Here we report that 60 prepubescent children showed the same sex difference and the same r elationship as adults between FRC and task performance: girls and L > child ren performed a female favouring task better while boys and R > children pe rformed a male-favouring task better. This finding indicates that these sex -related task performance differences are not dependent on the activational effects of adult gonadal steroids. The implications of these findings for prenatal influences on neuropsychological development are discussed.