THE INFLUENCE OF LONG-TERM PRACTICE ON MENTAL ROTATION OF 3-D OBJECTS

We evaluated the influence of long-term practice on the performance of a mental rotation task in which subjects judged whether two 3-D objec ts presented in different orientations were identical. Stimuli and exp erimental conditions were analogous to those used by Shepard and Metzl er. Sixteen subjects were selected, to test the influence of aptitude for mental imagery on this learning process. Subjects participed in 12 to 15 sessions over 6 weeks. Two catalogues of different stimuli were alternatively used during three (or six) consecutive sessions to dete rmine the influence of complexity and familiarity of figures. For all subjects, the inverse of the velocity of mental rotation along the ses sions was adequately fitted by a decreasing exponential curve. However , evidence for mental rotation did not disappear, even after 15 sessio ns. Asymptotic variations can be attributed to differences in stimuli as well as imaging skills of subjects. Our results lead to a new inter pretation of the mental rotation process.