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Abstract. Three different visual skills, along with Chinese character recognition, vocabulary, speeded naming, and syllable deletion skills were tested twice over one school year among 118 Hong Kong and 96 Xiangtan, China kindergartners. Results revealed that a task of Visual Spatial Relationships [Gardner, M. F. (1996). Test of visual-perceptual skills (Non-motor): Revised manual. Hydesville, CA: Psychological and Educational Publications] predicted unique variance in Chinese character recognition, controlling for other skills, at Time 1 among Hong Kong children and at Time 2 in Xiangtan children. The three visual skills were inconsistently affected by age and reading skill. Across testing times, visual skills of the Xiangtan children, who learn simplified script, were significantly higher than those of the Hong Kong children, learning traditional script. Results suggest a bidirectional association of visual skills with Chinese character acquisition across scripts.

We measured brain activity during mental rotation and object recognition with objects rotated around three different axes. Activity in the superior parietal lobe (SPL) increased proportionally to viewpoint disparity during mental rotation, but not during object recognition. In contrast, the fusiform gyrus was preferentially recruited in a viewpoint-dependent manner in recognition as compared to mental rotation. In addition, independent of the effect of viewpoint, object recognition was associated with ventral areas and mental rotation with dorsal areas. These results indicate that the similar behavioral effects of viewpoint obtained in these two tasks are based on different neural substrates. Such findings call into question the hypothesis that mental rotation is used to compensate for changes in viewpoint during object recognition.

Based on the geon structural description approach, I. Biederman and P.C. Gerhardstein (1993) proposed 3 conditions under which object recognition is predicted to be viewpoint invariant. Two experiments are reported that satisfied all 3 criteria yet revealed performance that was clearly viewpoint dependent. Experiment 1 demonstrated that for both sequential matching and naming tasks, recognition of qualitatively distinct objects became progressively longer and less accurate as the viewpoint difference between study and test viewpoints increased. Experiment 2 demonstrated that for single-part objects, larger effects of viewpoint occurred when there was a change in the visible structure, indicating sensitivity to qualitative features in the image, not geon structural descriptions. These results suggest that the conditions proposed by I. Biederman and P.C. Gerhardstein are not generally applicable, the recognition of qualitatively distinct objects often relies on viewpoint-dependent mechanisms, and the molar features of view-based mechanisms appear to be image features rather than geons.

The use of outline shape in recognizing objects was investigated in four experiments. In Experiment 1, subjects matched a shaded image to either another shaded image or a silhouette. In Experiment 2, subjects initially named shaded images; later they named either shaded images or silhouettes. Performance in both experiments was predicted by changes in the outline shape of the stimuli. The same matching (Experiment 3) and priming (Experiment 4) paradigms were then used to investigate recognition with objects that were rotated between presentations so as to change the outline shape of the object. Recognition was predicted by changes to outline shape. These results place constraints on models of object recognition, and are most compatible with viewpoint-dependent models of recognition.