Contrast and depth perception: effects of texture contrast and area contrast

Many objects in natural scenes have textures on their surfaces. Contrast of the texture surfaces (the texture contrast) reduces when the viewing distance increases. Similarly, contrast between the surfaces of the objects and the background (the area contrast) reduces when the viewing distance increases. The texture contrast and the area contrast were defined by the contrast between random dots, and by the contrast between the average luminance of the dot pattern and the luminance of the background, respectively. To examine how these two types of contrast influence depth perception, we ran two experiments. In both experiments two areas of random-dot patterns were presented against a uniform background, and participants rated relative depth between the two areas. We found that the rated depth of the patterned areas increased with increases in texture contrast. Furthermore, the effect of the texture contrast on depth judgment increased when the area contrast became low.     

Development of chromatic induction in infancy

The perception of colour in an embedded field is affected by the surround colour. This phenomenon is known as chromatic induction. In the present study we investigated whether the colour perception by infants aged 5–7 months could be affected by the surround colour. In Experiments 1 and 2 each stimulus was composed of an array of six squares in tandem. The colour appearance of the array in the familiarization stimulus was established by chromatic induction. In Experiment 1 we used familiarization stimuli that were perceived as two‐colour array with a two‐colour surround. In Experiment 2 we used a familiarization stimulus that was perceived as a uniform‐colour array with a two‐colour surround. In the test phase, the uniform‐colour array and the two‐colour array were presented on a white uniform‐colour surround in both experiments. The results showed that in Experiment 1 the 5‐ and 7‐month‐old infants had novelty preference for the uniform‐colour test array. This suggested that the infants' colour perception could be affected by surround colour. The results of Experiment 2 showed that the 7‐month‐olds showed a novelty preference for the two‐colour test array, but the 5‐month‐olds showed no novelty preference. This suggested that 7‐month‐olds' colour perception could be affected by surround colour, but that of 5‐month‐olds could not. We discuss the contradiction of the results between Experiments 1 and 2. Copyright © 2007 John Wiley & Sons, Ltd.     

Stereotypical Attitudes Toward Gender-Based Grade-Level Assignment of Japanese Elementary School Teachers

In Japanese elementary schools, principals and vice-principals determine the assignment of teachers to lower, upper, or middle grades. In this study, we examined principals' and vice-principals' attitudes toward gender in grade placement of teachers. The results showed that an overwhelming majority of principals and vice-principals held the stereotypical attitude that women are best suited to teach lower grades and men are best suited to teach upper grades. Moreover, we assumed that this attitude was related to perceptual distortions or stereotyping by principals and vice-principals regarding women's teaching preferences and women teachers' leadership ability.     

Phonology in the bilingual Stroop effect

In a bilingual Stroop task, we examined between-language interference among proficient Japanese-English bilingual speakers. Participants named ink colors either in Japanese or in English. The Japanese color terms were either phonologically similar to (i.e., loan words) or dissimilar from (i.e., traditional color terms) English color terms. For both response languages, a significant between-language Stroop effect was found despite the orthographic dissimilarity between the languages. The magnitude of the between-language interference was larger with the phonologically similar terms. These findings implicate direct links connecting phonologically similar matching words in the lexicons of proficient bilingual speakers of dissimilar languages and imply that phonological processing in lexical access occurs even when the access is done unintentionally.