Abstract
This study examined the effects of age and sex on mental rotation performance, verbal performance, and brainโwave activity. Thirtyโtwo 8โyearโolds (16 boys) and 32 college students (16 men) had EEG recorded at baseline and while performing four computerized tasks: a twoโdimensional (2D) gingerbread man mental rotation, a 2D alphanumeric mental rotation, of threeโdimensional (3D) basketball player mental rotation, and lexical decision making. Additionally, participants completed a paperโ and pencil water level task and an oral verbal fluency task. On the 2D alphanumeric and 3D basketball player mental rotation tasks, men performed better than boys, but the performance of women and girls did not differ. On the water level task, men performed better than women whereas there was no difference between boys and girls. No sex differences were found on the 2D gingerbread man mental rotation, lexical decisionโmaking, and verbal fluency tasks. EEG analyses indicated that men exhibited left posterior temporal activation during the 2D alphanumeric task and that men and boys both exhibited greater left parietal activation than women and girls during the 2D gingerbread man task. On the 3D basketball player mental rotation task, all participants exhibited greater activation of the right parietal area than the left parietal area. These data give insight into the brain activity and cognitive development changes that occur between childhood and adulthood. ยฉ 2002 Wiley Periodicals, Inc. Dev Psychobiol 40: 391โ407, 2002. Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/dev.10039