Evaluating the impact of depth cue salience in working three-dimensional mental rotation tasks by means of psychometric experiments

The gender difference in three-dimensional mental rotation is well documented in the literature. In this article we combined automatic item generation, (quasi-)experimental research designs and item response theory models of change measurement to evaluate the effect of the ability to extract the depth information conveyed in the two-dimensional illustrations on (1) females and males test performance and (2) subsequent cognitive processes called upon in the course of working three-dimensional mental rotation tasks. On the basis of prior studies we hypothesized that experimentally increasing the salience of depth cues would lead to an improvement in respondents' test performance that is more pronounced in females than males. This hypothesis was tested and confirmed in the first study. In the second study we extended the experimental design to take respondents' mental transformation strategies into account. We hypothesized that increasing the salience of depth cues would also lead to changes in respondents' mental transformation strategies. One of the main findings of this study was an increased use of more efficient mental transformation strategies that was more pronounced in females than males. Furthermore, the induced shift to more effective mental transformation strategies accounted for a sizeable portion of the reduction of the gender gap. The implications of the results of both studies are discussed.

Research highlights
► Possible explanation of the gender gap in mental rotation.
► Ensuring gender fairness by means of automatic item generation.
► Using IRT-Methods of change measurement to test and compare experimental hypotheses.