Gender differences in illusion response: The influence of spatial strategyand sex ratio

Two experiments explored factors related to gender differences in Ponzo ill usion susceptibility In Experiment 1, 54 male and 54 female (predominantly white, middle class) undergraduates were administered Witkin's Embedded Fig ures Test (EFT) and, on 2 separate occasions, a form of the Ponzo illusion. Results showed the Ponzo to be quite reliable over several days. Females w ere significantly more field dependent (as shown by slower responses to the EFT), and significantly more susceptible to the Ponzo illusion, than males . Furthermore, EFT performance correlated significantly with Ponzo suscepti bility, for females, but not for males, suggesting that the difference betw een males and females in Ponzo response may be due not to differences in fi eld independence per se, but rather to differences in the strategies used t o solve the illusion task. In Experiment 2, 111 male and 148 female (predom inantly white, middle class) undergraduates were administered the Ponzo ill usion twice, the 2 administrations separated by about 90 min. Again, the il lusion task showed good reliability, and females were significantly more su sceptible to the illusion. Furthermore, the magnitude of the difference bet ween males and females was systematically related to the sex ratio (the rat io of the number of males to the number of females) of the particular sessi on in which each subject happened to be participating. It is suggested that social factors such as sex ratio might affect the strategies participants use when doing illusion tasks, and perhaps other spatial skills tasks as we ll.