Sex differences on the hand mental rotation task for 9-yr.-old children and young adults.

The Hand Mental Rotation task is assumed to activate an egocentric spatial reference frame to realize mental rotation. This study presents significant sex differences in hand mental rotation performances between men and women (n = 23 and 25, respectively; age: 20.7 yr.). Differences in hand mental rotation in school girls and boys (ns = 48 and 41, respectively; age: 9 yr.) were not significant. Our results suggest that the change in sex differences in egocentric mental rotation may occur with developmental change. This requires further testing with a larger sample so testing can occur at several ages between 9 and 20.7 years.