On the identification of misoriented objects: Effects of task and level ofstimulus description

Three experiments are reported that examined the effects of misorientation in-the-plane on identification of natural objects and artifacts. Performanc e was tested in three tasks requiring the assignment of base level names, s uperordinate names and subordinate names to objects, respectively. The effe cts of misorientation varied as a function of the task, with stronger effec ts apparent on base level and subordinate level naming than on naming at th e superordinate level, and stronger effects on subordinate than on base lev el naming. Rotation effects, when they occurred, were additive with effects of stimulus category. These results suggest that object identification can proceed in parallel with processes that normalise misoriented stimuli, but the object descriptions derived without normalisation are coarse and consi stently sufficient only for superordinate classification. Before finer-grai ned identification processes can operate for base level or subordinate nami ng of both natural objects and artifacts, some form of normalisation is req uired. However, normalisation is not necessary for object descriptions to a ccess stored knowledge.