| dc.description | Naming latencies for objects rotated in the picture plane increase linearly as a function of object orientation for rotations up to 120$\sp\circ.$ This systematic effect of orientation is commonly thought to reflect angular normalisation of the image to the upright via the shortest angular distance prior to identification. A pre-identification process of normalisation is logically circular because image orientation is defined by the identity of the object, making the selection of the direction of rotation identity-dependent. Upright picture-name match/mismatch tasks have shown that objects are initially identified at a basic categorical level, while subordinate identification is delayed by further visual processing of the image. A series of studies employing name-rotated picture match/mismatch decisions and rotated object naming are presented in which the level of object identification was manipulated. The latency and accuracy results suggest that basic level identification is orientation invariant, while subordinate identification requires normalisation. Initial invariant access to a basic level identity would provide the object's current and upright orientation, allowing for the selection of the direction of rotation required for subordinate identification. This result challenges several current theories of object recognition concerning when normalisation of orientation occurs during rotated object identification. | en_US |
