Literature on mental rotation tasks consistently reports that males perform better than females. The current study is an attempt to scrutinize the influence of culture and experience with spatial activities in performance on a mental rotation test. The participants were 115 Ecuadorians, 120 Irish Caucasians and 128 Japanese. Half the participants In each group were male and half were female. They completed the Group Mental Rotation Test (GMRT) and a Spatial Activities Questionnaire (SAQ). Males outperformed females on the GMRT in all three cultures. Participation in "masculine activities" from the SAQ correlated with high GMRT scores, in "feminine activities" with low GMRT scores. There was a main effect of nationality; subjects from Ireland and Japan scored higher than their counterparts in Ecuador. The implications of the nationality effect raises questions about the widely accepted stability of the gender difference in spatial ability.

Key words: mental rotation, gender differences, cross-cultural study