ORIENTATION-INVARIANT TRANSFER OF TRAINING IN THE IDENTIFICATION OF ROTATED NATURAL OBJECTS

The effects of stimulus orientation on naming were examined in two exp eriments in which subjects identified line drawings of natural objects following practice with the objects at the same or different orientat ions. Half the rotated objects were viewed in the orientation that mat ched the earlier presentations, and half were viewed at an orientation that mismatched the earlier presentations. Systematic effects of orie ntation on naming time were found during the early presentations. Thes e effects were reduced during later presentations, and the size of thi s reduction did not depend on the orientation in which the object had been seen originally. The results are consistent with a dual-systems m odel of object identification in which initially large effects of diso rientation are the result of a normalization process such as mental ro tation, and in which attenuation of the effects is due to a shift from the normalization system to a feature/part-based system.