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41.
The current studies were designed to investigate the influence of variations in type of school setting on the development of role-taking skills and ethnic identity. We were interested in groups of school children in grades 1 to 5 inclusive from three different types of language programs: (1) instruction in the native language (English in this case); (2) total instruction in a second language (French); and (3) partial instruction in a second language (French). All children were native-English speaking, and came from perdominantly middle class families with monolingual English-speaking parents. The children from each program were equated at each grade level on age, and verbal and non-verbal I.Q. It was expected that (1) children in the second language programs would develop identity with their native language reference group later and less consistently than children in the native language programs; because (2) the second language children would identify more with the second language ethnic group; (3) the second language children would be able to understand at an earlier grade level than the native language group the principle of reciprocity in role-taking; and (4) these difference would be more pronounced for the totally than for the partially immersed second language children. The children were required to rate a number of ethnic dolls on a 20 point rating scale according to (1) how much each would be desired as a personal friend, (2) how much each would be desired as a friend for a member of another specific ethnic group, and (3) how similar each doll was to the child. The results indicated general support for hypotheses (1), (2) and (4), particularly among the primary school samples (1, 2), but a lack of support for hypothesis (3). These results demonstrate the influence of socio-cultural factors on the development of ethnic identity and ethnic role-taking skills. 相似文献
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Pranayama is a Yogic breathing practice which is known experientially to produce a profound calming effect on the mind. In an experiment designed to determine whether the mental effects of this practice were accompanied by changes in the arterial blood gases, arterial blood was drawn from 10 trained individuals prior to and immediately after Pranayama practice. No significance changes in arterial blood gases were noted after Pranayama. A neural mechanism for the mental effects of this practice is proposed. 相似文献
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This paper describes a software system called PLE that is designed to turn a Data General Corporation computer system into a sophisticated infinite-channel tachistoscope. We describe hardware and software characteristics of the PLE system and evaluate its performance in comparison to a typical tachistoscope. Additionally, we describe two example experiments that have been implemented in the PLE system. 相似文献
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Ronald S. Harwerth Earl L. Smith Dennis M. Levi 《Attention, perception & psychophysics》1980,27(1):43-50
Binocular interactions of suprathreshold grating patterns have been investigated using a reaction time measure of contrast detection. Simple reaction times were determined for monocular and binocular viewing conditions over a contrast range from .63 to near threshold. The results from all subjects showed binocular summation for contrast levels near threshold, but there was considerable variation across subjects for contrast levels above threshold. Some subjects showed summation over the entire contrast range, but other subjects showed either binocular inhibition or binocular facilitation for some range of contrast levels. The pattern of binocular interaction for a given subject was consistent for several spatial frequencies. The differences in types of interaction between subjects, the variation in magnitude of binocular interaction with contrast level for each subject, and the data from experiments involving stimulation of noncorresponding retinal areas show that the binocular interactions found for suprathreshold stimuli cannot be accounted for on the basis of probability, and must, therefore, result from physiological interactions between the two eyes. These interactions have been investigated further under conditions of (1) induced fixation disparity, (2) horizontal gratings, and (3) orthogonally oriented gratings. 相似文献
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Previous work has shown that adults and older children tend to classify multi-dimensional objects by identity on one dimension, whereas children under 8 years of age tend to classify these same objects by a relation of overall similarity. The present study investigated the hypothesis that this developmental trend is restricted to the classification of simple objects that differ only by limited amounts on a few dimensions. The specific hypothesis was that overall-similarity relations structure both adults' and children's classifications of heterogenous objects (objects that differ in a variety of ways). This hypothesis was suggested by the correspondence between the structure of young children's classifications and the structure of natural categories. The result of two experiments supported the hypothesis. When the to-be-classified objects varied simultaneously on relatively many dimensions, adults as well as children constructed classifications that maximized within-category similarity on all varying dimensions. The implications of these results for accounts of the perception of multidimensional relations and classificatory behavior are discussed. 相似文献
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I Rock D Smith 《Journal of experimental psychology. Human perception and performance》1981,7(1):19-29
It has been assumed that certain stimulus transformations lead directly to depth effects, that is, that such transformations are the necessary and sufficient conditions for kinetically generated depth perception. An alternative is to view such perception as the preferred solution to the problem posed by the transforming stimulus as to what even in the world is producing that transformation. In several experiments it is shown that when other solutions are supportable by the stimulus, those same transformations will no longer lead to depth perception. These other solutions become preferred on the basis of rejection of certain coincidental features of the stimulus that otherwise would have to be accepted were the kinetic depth solution to be maintained. The findings are interpreted as challenging any theory that perception is simply the direct result of stimulation or of extraction of stimulus information and as supporting the Helmkoltzian rule of perception as a construction of the most reasonable representation. 相似文献
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