ROTATING OBJECTS TO RECOGNIZE THEM - A CASE-STUDY ON THE ROLE OF VIEWPOINT DEPENDENCY IN THE RECOGNITION OF 3-DIMENSIONAL OBJECTS

Successful object recognition is essential for finding food, identifying kin, and avoiding danger, as well as many other adaptive behaviors. To accomplish this feat, the visual system must reconstruct 3-D interpretations from 2-D ''snapshots'' falling on the retina. Theories of recognition address this process by focusing on the question of how object representations are encoded with respect to viewpoint. Although empirical evidence has been equivocal on this question, a growing body of surprising results, including those obtained in the experiments presented in this case study, indicates that recognition is often viewpoint dependent. Such findings reveal a prominent role for viewpoint-dependent mechanisms and provide support for the multiple-views approach, in which objects are encoded as a set of view-specific representations that are matched to percepts using normalization procedures.