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This study examined how children used shape similarity information when they inferred the meaning of a novel label which was given to a familiar object. When children were shown two objects similar only in shape (white paper cup and glass), 5 : 7- to 6 : 7-year-old children (N = 28, M = 5 : 11) assigned the novel label only to the object identical to the target, whereas 4 : 7- to 5 : 6-year-old children (N = 28, M 4 : 11) mapped the novel label to all objects within the familiar object category. When children of both age groups (N = 15, M = 5 : 8, range = 5: 3 to 6 : 2; N 12, M = 4 : 10, range = 4 : 3 to 5 : 1) were shown two paper cups identical except color (white paper cup and pink one), children selected both of the two objects. These results showed children in both age groups regarded the objects identical except color as those given the same label; on the other hand, children did not think of the objects similar only in shape as qualified for the same label. Therefore the results imply that what is treated as "shape similarity" in this area of research includes the similarity not only in shape but also in other dimensions such as material.

It is an open question how simple features are integrated in the attention spotlight. In this paper, we examined two opposing models for the integration process of shape and color. One is a local conjunction model in which simple features of shape and color are combined directly. The other is a whole conjunction model in which simple features of shape are integrated into the whole shape and then it is combined with color. In Experiment 1, we measured the time required to search for a target defined by a conjunction of shape and color for five subjects with changing coloring of the figures. The slope of the search function was gentler when corners of figures were colored (p < 0.01). In Experiment 2, we measured the time required to integrate shape and color of figures presented in rapid serial visual presentation (RSVP) for five subjects. The presentation time required to answer the correct combination was shorter when corners were colored (p < 0.01). These results support the local conjunction model.

This paper was to examine the spatial extent of the Contralateral Suppressive Field by using a probe stimulus (20' in diameter) method. It was found that (a) the suppressive effect, measured by frequency of phenomenal disappearance of the probe stimulus, declined sharply in proportion to the distance from the contour of the suppressor, and it declined more sharply near the center of the visual field and (b) the same effect increased in proportion to the contrast of the suppressor, but was independent of the width of the suppressor.