Directional biases in adults' performance on a multiple-choice water-level task

Sex Differences in Visual-Spatial Performance among Ghanaian and Norwegian Adults

Sex differences in spatial ability among adults in Western cultures are widely acknowledged, but few studies have assessed visual-spatial ability in non-Western subjects with tests that show the largest sex differences, and little is known whether effect sizes for different spatial ability categories are the same across cultures. This issue was addressed by using four visual spatial ability tests (water level, surface development, PMA space, and Vandenberg-Kuse) to collect data from university students in Ghana (n = 197) and Norway (n = 220). Except for the Surface Development test, on which no sex difference appeared in either sample, males perforned significantly better than females in both samples, and the effect sizes (r) were about medium, with no significant between-nationality difference on individual tests. These results showed that patterns and magnitudes of sex differences in spatial abilities were simiilar across cultures. The test intercorrelation patterns in the two samples differed markedly, suggesting that the ability structure underlying spatial performance may be different in the two cultures.

A Comparison of Sex Differences in Visual-Spatial Performance from Preadolescence to Adulthood in Ghana and Norway

This study examined sex-related differences in visual-spatial performance from a cross-cultural perspective by comparing cross-sectional data on four visual-spatial tests (measuring three spatial ability categories) on four different age groups (9, 12, 16 and adults) in Ghana and Norway. Reliable sex differences in favor of males were present in all age groups and their effect size magnitudes were practically constant over age in the two cultures. There were significant differences in the test intercorrelations in the two samples, suggesting that different structures of abilities may underlie spatial task performance in the two cultures. The results do not support the notion that the development of sex differences in spatial abilities is dependent on maturational or psychosocial processes. The near adult effect size by age 9 and the stability of the magnitude across cultures, argue for a biologically-based explanation of the observed sex differences in spatial performance.