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41.
Five-year-old children were tested for perceptual trading relations between a temporal cue (silence duration) and a spectral cue (F1 onset frequency) for the “say-stay” distinction. Identification functions were obtained for two synthetic “say-stay” continua, each containing systematic variations in the amount of silence following the /s/ noise. In one continuum, the vocalic portion had a lower F1 onset than in the other continuum. Children showed a smaller trading relation than has been found with adults. They did not differ from adults, however, in their perception of an “ay-day” continuum formed by varying F1 onset frequency only. The results of a discrimination task in which the two acoustic cues were made to “cooperate” or “conflict” phonetically supported the notion of perceptual equivalence of the temporal and spectral cues along a single phonetic dimension. The results indicate that young children, like adults, perceptually integrate multiple cues to a speech contrast in a phonetically relevant manner, but that they may not give the same perceptual weights to the various cues as do adults.  相似文献   
42.
Three experiments are described which elaborate some of the conditions under which rats will contact and manipulate a periodically presented retractable lever. Experiment 1 demonstrated that (i) initial manipulative oral and manual contact with the lever was facilitated if the rat had previous experience of food delivery in the experimental chamber; (ii) persistence in contacting the lever on successive presentations was a function of whether food continued to be presented in the experimental environment; and (iii) food satiation significantly reduced the tendency of the rat to contact the lever even though an expectancy of food had previously been established under conditions of food deprivation. Experiment 2 suggested that the tendency to approach and contact the lever was in part a function of the local moment-to-moment conditional probability of food delivery. Experiment 3 found that the probability of contacting the lever was higher during presentation of an auditory CS signaling a high rate of food delivery than during stimuli signaling no food at all. These results are interpreted as suggesting that the food-signaling aspects of an appetitive CS and that CS's ability to generate signal-directed behaviors are experimentall separable properties.  相似文献   
43.
The effects of flavor preexposure and test interval on conditioned taste aversions were examined in four experiments. In the first three experiments, prior experience with a flavor different from that used as a conditioned-stimulus (CS) produced attenuated aversions when testing occurred after a 1-day interval but not after a 21-day interval. Preexposure to the same stimulus used as a CS produced attenuated aversions at both 1- and 21-day intervals. In Experiment 4, a delay interval between flavor preexposure and conditioning eliminated the attenuating effect of preexposure, but only when different stimuli were used for preexposure and conditioning. These data could not be easily accounted for by contemporary interpretations of preexposure as an event that interferes with subsequent acquisition of a conditioned aversion. An alternative retrieval interference hypothesis was outlined.  相似文献   
44.
大学生镜像书写及其机制探讨   总被引:1,自引:0,他引:1  
本研究选择60名右利大学生(男女各半)为被试,在笔划水平上对十四种不同书写方式下快速书写时所出现的自发性镜像书写进行了研究。所有被试随机分为人数相等的实验、对照两组,组内男女各半。对实验组加以注意干扰。书写内容是十个阿拉伯数字(0—9)及十三个汉字组成的一句话。本研究结果表明:注意干扰、感觉的反馈调节,书写内容的特点是影响镜像书写出现的重要因素。作者在分析国内外有关镜像书写工作的基础上,进一步提出了“稳态系统”理论。  相似文献   
45.
An adult, with a puppet held at shoulder height on either side (within the infant's visual field), interacted with 3- to-6-month-olds, turning her head intermittently to talk to a puppet. Seventy- three percent of infants' first eye-turns were in the direction of the adult head-turn.  相似文献   
46.
A multidisciplinary group of genetic and other professionals discuss a complex case of familial conflict over access to genetic information. One twin wishes to know the results of her deceased mother's tests for BRCA1 mutations; a second twin objects to researchers making this information available. As the case discussion unfolds, the apparent facts of this case are called into question and the lines of ethical certainty become less clear.  相似文献   
47.
The cloning of BRCA1, a susceptibility gene for inherited breast cancer, has made genetic screening possible for individuals and families whose medical histories are suggestive of an inherited predisposition to breast cancer. To date, few systematic attempts have been made to determine the level of knowledge about breast cancer genetics among women who are likely to seek BRCA1 screening when it becomes widely available. The present study attempted to assess the general knowledge about BRCA1 mutations in two groups: (1) first-degree relatives (FDRs) of breast cancer patients; and (2) women with a previous diagnosis of breast cancer. A self-administered, thirty-item questionnaire was developed through a pilot study. Ten of the items were objective, factual questions about breast cancer genetics. Responses to these questions were used to generate an overall knowledge score for each respondent. The study population was moderately knowledgeable about breast cancer genetics, with an average score of 5.35 out of 10. Counselors should not underestimate the importance of evaluating each counselee's existing knowledge about breast cancer, which can affect the provision and reception of genetic information. In particular, specific areas of knowledge that may be confusing or misunderstood were identified and these topics are discussed in detail.  相似文献   
48.
Relation algebras from cylindric and polyadic algebras   总被引:1,自引:0,他引:1  
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49.
This compound paper presents the views of two Polish philosophers on the strong international pressures influencing the development of Polish philosophy in recent times. The first part, by Leszek Koczanowicz, treats the philosophical situation and problems of totalitarian Poland under the influence of Soviet Marxism, while the second part, by Adam Chmielewski, focuses on the main trends and difficulties of post-totalitarian Poland, dominated by Western influence.  相似文献   
50.
Passport to Duke     
Editor’s Introduction The following text was prepared by Pierre Bourdieu for delivery at a conference on his work held at Duke University, April 21–23, 1995. Entitled “Pierre Bourdieu: Fieldwork in Culture,” the conference was sponsored by the Duke Graduate Program in Literature and included such well-known literary scholars as Barbara Herrnstein Smith, Jonathan Culler, and Fredric Jameson. Bourdieu, of course, was the invited guest of honor, but was uncertain as to whether he should make the effort of attending, particularly since he was recovering from a short period of poor health. As I too had been invited (and seemed more familiar with the American scene), Bourdieu discussed the question with me in Paris. He was rather concerned about wrongheaded, trendy applications of his theories by American literary scholars, who often misunderstand his work because they simply do not know the intellectual landscape to which it relates. Reading such conference paper titles as “Cross-Dressing for Success: The Scramble for Symbolic Power in Tabitha Sweeney’s Female Quixotism,” Bourdieu confessed his fear of being taken as simply the French intellectual flavor of the month, one whose theory is used simply as grist for the American academy’s industrious mills of literary interpretation. He ultimately decided to send the following text to be read at the conference in his absence. It treats, with polite frankness, his worries about being misinterpreted through importation into the American theoretical field with its peculiar conception of French philosophy; Bourdieu’s paper situates these particular worries within a more general account of “allodoxic”distortions caused by the international travel of theory; but it also tries to prevent further misunderstanding by offering a brief contextualization of his theory and a brief summary of his method of analysis through fields. The translation of Bourdieu’s text was prepared by Loïc Wacquant, and is presented here with only minor adjustments.  相似文献   
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