On the perception of objects and their orientations

A novel paradigm, description-depiction classification (DDC), was used to test whether knowledge of object orientation in the picture plane precedes or follows object identification. Undergraduate students were asked to verify the identities and orientations of depicted objects against preceding descriptions, e.g. 'UPRIGHT CAR'. The results showed that identity mismatches were verified faster and more accurately than orientation mismatches, regardless of whether subjects had to discriminate small (90 deg) or large (180 deg) differences in orientation. These findings suggest there is primacy for identity information in that (a) subjects determine object identity before they determine object orientation, and (b) even when orientation is determined, identity information tends to dominate the response. This is the signature of a perceptual-cognitive system that has evolved to rapidly identify objects, not their orientations, contra to theories of recognition that assume orientation is determined before an object has been classified at the basic level.