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Rats were trained in a three-alternative spatial delayed matching-to-sample task in a starburst maze. Samples consisted of rewarded forced choices of one arm, and retention was indicated by rats’ returning to that arm after a 90-sec delay. If a rat made an error on its first choice, it was returned to the start compartment and allowed a second choice. Unlike in previous experiments with this task, all three arms were available during the animals’ second choices. The rats tended to perseverate in their second choices by returning to the arm that they had erroneously visited on their first choice. In Experiment 1, the accuracy of second choices following first-choice errors was below chance during the first block of sessions, when a 90-sec delay intervened between the first choice and the second choice, and at chance during the second block of sessions, when a short (5–6 see) delay intervened between first and second choices. In Experiment 2, long-delay and short-delay sessions were randomly presented to naive subjects. Similar results were obtained. In both experiments, the tendency to repeat the erroneous first choice was greater when long delays separated the two choices than when short delays were used. The results suggest that rats make their first-choice errors because they erroneously encode or remember the location of the sample and that they base their second choices on the same erroneous-memory. The increase in perseveration at long delays implies some kind of rehearsal-like mechanism that slows forgetting of the memory controlling the first choice. 相似文献
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Selective universities regularly employ policies that favor children of alumni (known as legacies) in undergraduate admissions. Since alumni from selective colleges and universities historically have been disproportionately white, admissions policies that favor legacies have disproportionately benefited white students. For this reason, legacy policies lead to additional costs in terms of reductions in racial diversity. As larger numbers of minority students graduate from colleges and universities and have children, however, the potential pool of legacy applicants will change markedly in racial composition. This analysis begins with a review of the history and objectives of the preference for children of alumni in undergraduate admissions. We then consider the specific case of the University of Virginia and employ demographic techniques to predict the racial composition of the pool of potential legacy applicants to the university. Significant changes in the racial composition of classes that graduated from the University of Virginia from the late 1960s through the 1970s foreshadow similar changes in the characteristics of alumni children maturing through the next two decades. 相似文献
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This study investigated the effects of a brief meditation intervention on perceived stress, mindfulness, and sleep quality for college freshmen who have aged out of foster care. Thirty-six youth who had aged out of foster care and enrolled at a large midwestern 4-year university (n?=?16 experimental group, n?=?20 control group) participated in a study in which they were assessed three times on the dependent variables. Students also participated in a focus group after the intervention ended. Four sessions of the brief mindfulness intervention resulted in significant short-term reductions in stress levels and increases in sleep quality. Finding effective personal interventions to increase chances for college success for students with histories in foster care can also offer potential insight toward the development of educational models and resources for other vulnerable college student populations. 相似文献
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AbstractThis study sought to determine if human papillomavirus (HPV) vaccination rates are associated with teaching requirements for abstinence in state sex education laws and policies. A cross-sectional analysis was conducted assessing the association between abstinence education legislation and HPV vaccination rates in adolescents (aged 13–17?years). After adjustment for insurance coverage and household income, the level of abstinence education was not significantly associated with vaccination rates. However, a higher percentage of individuals uninsured was significantly and negatively associated with the vaccination rate. This suggests that HPV vaccination rates are associated with insurance coverage, but not with the degree to which sex education laws or policies emphasize abstinence. 相似文献
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Marilyn P. Arnone Ruth V. Small Sarah A. Chauncey H. Patricia McKenna 《Educational technology research and development : ETR & D》2011,59(2):181-198
This paper identifies the need for developing new ways to study curiosity in the context of today’s pervasive technologies
and unprecedented information access. Curiosity is defined in this paper in a way which incorporates the concomitant constructs
of interest and engagement. A theoretical model for curiosity, interest and engagement in new media technology-pervasive learning
environments is advanced, taking into consideration personal, situational and contextual factors as influencing variables.
While the path associated with curiosity, interest, and engagement during learning and research has remained essentially the
same, how individuals tackle research and information-seeking tasks and factors which sustain such efforts have changed. Learning
modalities for promoting this theoretical model are discussed leading to a series of recommendations for future research.
This article offers a multi-lens perspective on curiosity and suggests a multi-method research agenda for validating such
a perspective. 相似文献
30.
Pavlo D. Antonenko Craig A. Ogilvie Dale S. Niederhauser John Jackman Piyamart Kumsaikaew Rahul R. Marathe Sarah M. Ryan 《Education and Information Technologies》2011,16(4):323-342
This paper describes the ways that students’ problem-solving behaviors evolve when solving multi-faceted, context-rich problems
within a web-based learning environment. During the semester, groups of two or three students worked on five physics problems
that required drawing on more than one concept and, hence, could not be readily solved with simple “plug-and-chug” strategies.
The problems were presented to students in a data-rich, online problem-based learning environment that tracked which information
items were selected by students as they attempted to solve the problem. The students also completed a variety of tasks, like
entering an initial qualitative analysis of the problem into an online form. Students were not constrained to complete these
tasks in any specific order. As they gained more experience in solving context-rich physics problems, student groups showed
some progression towards expert-like behavior as they completed qualitative analysis earlier and were more selective in their
perusal of informational resources. However, there was room for more improvement as approximately half of the groups still
completed the qualitative analysis task towards the end of the problem-solving process rather than at the beginning of the
task when it would have been most useful to their work. 相似文献