Seeing things from a different angle: The pigeon's recognition of single geons rotated in depth

In 2 experiments involving computer-rendered versions of single shapes or " geons," the extent to which depth rotation affects the visual discriminatio n performance of pigeons in both go/no-go and forced-choice tasks was docum ented. The pigeons were able to recognize geons at most rotations in depth: however, the pigeons' recognition performance was better at the training v iew than at most other views. Aspects of these results are both consistent with and problematic for object-centered and viewer-centered theories of ob ject. recognition.