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21.
Simultaneous auditory discrimination.   总被引:1,自引:1,他引:0       下载免费PDF全文
Stimuli in many visual stimulus control studies typically are presented simultaneously; in contrast the stimuli in auditory discrimination studies are presented successively. Many everyday auditory stimuli that control responding occur simultaneously. This suggests that simultaneous auditory discriminations should be readily acquired. The purpose of the present experiment was to train rats in a simultaneous auditory discrimination. The apparatus consisted of a cage with two response levers mounted on one wall and a speaker mounted adjacent to each lever. A feeder was mounted on the opposite wall. In a go-right/go-left procedure, two stimuli were presented on each trial, a wide-band noise burst through one speaker and a 2-kHz complex signal through the other. The stimuli alternated randomly from side to side across trials, and the stimulus correlated with reinforcement for presses varied across subjects. The rats acquired the discrimination in 400 to 700 trials, and no response position preference developed during acquisition. The ease with which the simultaneous discrimination was acquired suggests that procedures, such as matching to sample, that require simultaneous presentation of stimuli can be used with auditory stimuli in animals having poor vision.  相似文献   
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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   
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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   
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Im Anfang des 20.Jahrhunderts unterzog eine Reihe von jungen, später berühmt gewordenen Philosophen den Marxismus einer tiefen Kritik. Ihnen ist es gelungen, wichtige Defekte der revolutionären Doktrinen aufzudecken und ihre verhängnivsollen Konsequenzen vorwegzunehmen. Diese Kritik ist auch für die gegenwärtige geistig-politische Situation aktuell.  相似文献   
25.
对幼儿从电视中伴随学习单词的可能性及其影响因素进行了初步的探讨。40名小班幼儿和46名大班幼儿参加了实验,他们在接近自然的状态下观看有字幕的动画片。结果发现:幼儿在无任何指导的情况下观看有字幕的动画片,能伴随学习到汉字,这表明,电视对幼儿的词汇发展有着积极的影响;不同性别的儿童都能同等程度地从电视中伴随学习到单词;词义的伴随学习受幼儿原有的词汇水平和幼儿对目标词熟悉程度的影响;词音的伴随学习只发生在词汇水平较高的幼儿当中,并且随着幼儿对目标词熟悉程度的增加而增加;词音和词义的伴随学习存在频度效应。  相似文献   
26.
Two studies were conducted, the first to establish a valid Spanish version of the Daily Stress Inventory (DSI). A second study was conducted using the bilingual version of the DSI to assess differences in the level of stress experienced by three selected Hispanic groups: (a) very Hispanic/Hispanic-oriented bicultural, (b) true bicultural, and (c) Anglo-oriented bicultural/very Anglicized as determined by the adapted version of the Acculturation Rating Scale for Mexican Americans (ARSMA). It was expected that stress levels would be highest for the least acculturated group. The results of the first study indicate that the Bilingual DSI scores are highly correlated with the scores of the original DSI when both instruments are responded to simultaneously by fully bilingual individuals. In Study 2, the initial data analyses showed no difference in the level of stress reported by Hispanics at different levels of acculturation as measured by the ARSMA. When a median-split method was employed, differences in the DSI I/E measures between the two groups were significant, suggesting that acculturation level may be related to stress level.  相似文献   
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Gabriel Marcel was a French, Catholic, existential philosopher who first presented the concept of human availability as a central way of strengthening the self and facilitating the experience of human freedom. In this article Marcel's ideas about availability are described, reviewed, and examined for their implications for the practice of existential psychotherapy with couples and families.  相似文献   
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