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941.
Perceptual learning refers to the phenomenon that practice or training in perceptual tasks often substantially improves perceptual performance. Often exhibiting stimulus or task specificities, perceptual learning differs from learning in the cognitive or motor domains. Research on perceptual learning reveals important plasticity in adult perceptual systems, and as well as the limitations in the information processing of the human observer. In this article, we review the behavioral results, mechanisms, physiological basis, computational models, and applications of visual perceptual learning.  相似文献   
942.
The creation of the European Community by the Treaty of Rome in 1957 marked the beginning of the efforts to coordinate and harmonize national policies in many strategic sectors with high economic value, among them several aspects of scientific research. The European Union Law, formerly known as European Community law, now includes a range of ethical principles that apply to research projects developed with the financial support of the European Union. Which were the steps in the integration of the ethics of sciences in the context of the Union? This article aims to study first, what were, and what are the legal bases of the integration of the ethical dimension of researches in life sciences by the European Union and, secondly, the institutional organisation that has been set up in order to discuss the development of common ethical norms, especially bioethics one, and in order to apply these rules which respect national particularities. In this regard, we analyse the relevant legal texts providing a foundation for the creation of a European bio-law and we give an overview of the European institutions' activity in the field of bioethics by looking particularly the health research field.  相似文献   
943.
The aim of this study was to examine depression and anxiety disorders and their characteristic symptoms (anhedonia/low positive affect and anxious arousal, respectively), along with measures of state negative affect (NA) and Type D personality, in relation to cardiac surgery related morbidity. Patients awaiting elective coronary artery bypass graft surgery (n=158; 20.9% female; 11.4% concomitant valve surgery; age M=64.7, SD=10.6) underwent the structured MINI International Neuropsychiatric Interview to determine current affective disorders. Patients also completed the Mood and Anxiety Symptom Questionnaire and a measure of Type D personality traits. Postoperative cardiac morbidity was confirmed after surgery during the index hospitalization and included stroke,renal failure, ventilation>24 h, deep sternal wound infection, reoperation, arrhythmia and 30-day mortality at any location (n=59, 37.3% of total). After adjustment for age, recent myocardial infarction, heart failure, hypertension, urgency of surgery and time spent on cardiopulmonary bypass generalized anxiety disorder was associated with cardiac morbidity (odds ratio [OR]=3.26, 95% confidence interval [CI] 1.10-9.67, p=0.03). Adjusted analysis of personality traits revealed the NA component of Type D personality was associated with cardiac morbidity (OR=1.07, 95% CI 1.01-1.14, p=0.03). The Mood and Anxiety Symptom Questionnaire subscales were not associated with increased morbidity risk. Affective disorders, affective phenotypes, and personality traits were differentially associated with post-cardiac surgery morbidity outcomes independent of cardiac surgery morbidity risk factors. Concurrent investigation of depression and anxiety with respect to cardiac outcomes warrants further research.  相似文献   
944.
In adults, native language phonology has strong perceptual effects. Previous work has shown that Japanese speakers, unlike French speakers, break up illegal sequences of consonants with illusory vowels: they report hearing abna as abuna. To study the development of phonological grammar, we compared Japanese and French infants in a discrimination task. In Experiment 1, we observed that 14-month-old Japanese infants, in contrast to French infants, failed to discriminate phonetically varied sets of abna-type and abuna-type stimuli. In Experiment 2, 8-month-old French and Japanese did not differ significantly from each other. In Experiment 3, we found that, like adults, Japanese infants can discriminate abna from abuna when phonetic variability is reduced (single item). These results show that the phonologically induced /u/ illusion is already experienced by Japanese infants at the age of 14 months. Hence, before having acquired many words of their language, they have grasped enough of their native phonological grammar to constrain their perception of speech sound sequences.  相似文献   
945.
Contemplative Pedagogy is a new and sometimes controversial pedagogical practice. Faculty often have basic questions about how to implement the pedagogy in their classrooms, in addition to questions that challenge the educational value and appropriateness of the practice. Assembled here are the most frequently asked questions about Contemplative Pedagogy, with responses from six contemplative professors, each from a different institutional and philosophical location. The respondents are founding members of the Contemplative Studies Consultation of the American Academy of Religion. The diversity of views expressed by the respondents invites the reader to see that there is no single theory or praxis of contemplative pedagogy.  相似文献   
946.
College campuses are among the most racially diverse settings in our segregated society. For many students, especially non-Hispanic whites, college represents the first time they have come into significant contact with members of other groups. Using data from the National Longitudinal Survey of Freshmen, this paper explores the effects of campus diversity and various types of interracial contact on the racial and ethnic attitudes of white students over the course of four years in college. The findings are largely consistent with the contact hypothesis, particularly with respect to changes in attitudes towards blacks. White students who report having a close friend who is black and those who have dated or had a romantic partner who is black express less social distance towards blacks in their senior year, as do white students who were involved in extracurricular activities in which blacks are the majority. Participating in extracurricular activities dominated by blacks is also associated with more positive views of the impact of affirmative action on academic standards expressed as students were leaving college. Although there is evidence that both stereotypes and social distance towards groups are mitigated by intergroup contact, stereotypes appeared to be somewhat more resistant to change. The findings suggest that institutions should continue efforts to diversify their student populations, and also promote involvement in extracurricular activities for students from all groups.  相似文献   
947.
Educational research and practice could benefit from and contribute to multi-disciplinary study of well-being. In particular, research on the well-being of youth within and beyond school may benefit students, educators, administrators, and the community. This review provides a conceptual framework that (a) integrates research on well-being from economics, sociology, psychology and the health sciences, (b) organises this literature within seven domains of inquiry: Having, Being, Relating, Thinking, Feeling, Functioning, and Striving, and (c) highlights research pertinent to senior high school level educational experiences. This framework provides an important foundation from which further research on well-being can be developed.  相似文献   
948.
The effect of fear and anger on selective attention   总被引:1,自引:0,他引:1  
This experiment examined the effects of two discrete negative emotions, fear and anger, on selective attention. A within-subjects design was used, and all participants (N = 98) experienced the control, anger, and fear conditions. During each condition, participants viewed a film clip eliciting the target emotion and subsequently completed a flanker task and emotion report. Selective attention costs were assessed by comparing reaction times (RTs) on congruent (baseline) trials with RTs on incongruent trials. There was a significant interaction between emotion condition (control, anger, fear) and flanker type (congruent, incongruent). Contrasts further revealed a significant interaction between emotion and flanker type when comparing RTs in the control and fear conditions, and a marginally significant interaction when comparing RTs in the control and anger conditions. This indicates that selective attention costs were significantly lower in the fear compared to the control condition and were marginally lower in the anger compared with the control condition. Further analysis of participants reporting heightened anger in the anger condition revealed significantly lower selective attention costs during anger compared to a control state. These findings support the general prediction that high arousal negative emotional states inhibit processing of nontarget information and enhance selective attention. This study is the first to show an enhancing effect of anger on selective attention. It also offers convergent evidence to studies that have previously shown an influence of fear on attentional focus using the global-local paradigm.  相似文献   
949.
We created a novel eye movement version of the n-back task to measure spatial working memory (WM). Rather than one continuous trial, discrete trials were presented in order to develop a simpler WM task. In Experiment 1, we varied the visibility of the final stimulus to maximize the difference in performance between 0-back and 1-back tasks (WM effect). In Experiment 2, we administered the optimized task to children. In Experiment 3, we further simplified the task. Both adults and children easily completed our task, displaying significant WM effects. Further, similar WM effects were obtained in our original and simplified n-back spatial WM tasks, demonstrating flexibility. Because WM deficits are often an early feature of disease and a marker of disease progression, our saccadic measure of spatial WM may be particularly useful in hard-to-test populations, such as patients and children, and may have application in brain-imaging studies that require discrete trials.  相似文献   
950.
The aim of the present study was to expand the scope of category norm and typicality data to include verbs for use when investigating semantic memory in fields such as linguistics, psychology, and aphasiology. Two experiments were conducted. In the first, participants were asked to list verbs within 10 semantic categories (e.g. breaking, cleaning, cooking, etc.) and 10 noun categories (e.g. animals, fruit, tools, etc.). In the second experiment, participants were asked to rate the typicality of verbs within 8 of the previously investigated verb categories. Although participants listed fewer verbs in verb categories than nouns in noun categories, the overall patterns with regard to correlation analyses between production frequency, mean rank of responses, lexical frequency, and typicality were consistent with those observed in noun categories. These patterns are also consistent with those observed in previous research. Potential similarities and differences between nouns and verbs, as well as future applications of such data, are discussed.  相似文献   
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