Item type,occlusion, and gender differences in mental rotation

Two experiments were conducted to examine the role of item type in mental rotation. In each experiment, participants completed two computerized mental rotation tasks, one with blocks as stimuli and one with human figures as stimuli. The tasks were formatted either as a multiple-choice psychometric test (Experiment 1) or as a same–different type task (Experiment 2). Aside from the expected replication of a decreased effect of occlusion on women's accuracy when processing human figures compared to block figures, it was hypothesized that response times would increase when processing the complex but familiar human figures, compared to the simple but unfamiliar block figures. In Experiment 1, the results relevant to occlusion were replicated. However, the presence of a speed–accuracy trade-off suggested that participants processed human figures faster but less accurately than block figures. In Experiment 2, both men and women performed faster and more accurately when processing occluded human figures than when processing nonoccluded human figures. The effect of item type, its potential link to embodied cognition, and the role of strategy selection on gender differences in mental rotation are discussed.