Object constancy is essential to the manual interaction of an observer with various objects in the three-dimensional environment. In order to achieve object constancy, the employment of global structure is useful for natural objects, especially artifacts. Estimating the three-dimensional global structure of an object from two-dimensional retinal image depends on how an object-centered reference frame is assigned to the object. In the present study, we studied the effects of object discriminability based on global structure on the object identity matching of three-dimensional familiar objects from two different views: canonical view and non-canonical view. Three experiments were conducted: sequential matching (Experiment 1), simultaneous matching (Experiment 2), and sequential matching using silhouettes (Experiment 3). Findings are summarized as follows: 1) Global structure affected the matching performance differentially based on view canonicality; 2) The discrimination process based on global structure operates at the perceptual stage of recognition; and 3) The effectiveness of outline shape on the access to semantic knowledge depended on view canonicality. These results suggest that the global structure of an object is stored in semantic knowledge, and serves as the basis of recognition of familiar objects. Since the global structure of an object in the natural environment is easily obtained, object recognition based on global structure underlies rapid performance in everyday life.
