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981.
982.
Immediately after a recently fed rodentdemonstrator interacts with a conspecificobserver, the observer shows a substantially enhanced preference for whatever food its demonstrator ate. Here we show that (1) influence
of a single, 30-min interaction with a demonstrator on an observer’s food preference lasts for at least 1 month, and (2) observers
interacting on 2 successive days with a demonstrator fed a different diet on each day show significantly enhanced preferences
for both diets a month later. Such enduring effects of single, brief interactions between a demonstrator rat and its observer
provide an efficient means for studying physiological and behavioral substrates of long-term memory in rodents. Together with
the results of previous studies of social influences on food choices of rats, the present results also suggest that rats may
use information acquired from conspecifics to identify both toxic and safe foods for many weeks after they have acquired this
information. 相似文献
983.
984.
985.
Eating rates (bites per interval) and other meal behaviors (number of chews, sips, talks with a neighbor, and chews per bite) were observed for 30 normal and 30 overweight white preschool children in their school cafeterias. Children were classified according to weight (overweight or normal), age (1 1/2--2 years, 3--4 years, or 5--6 years) and sex. Analysis of variance revealed that overweight preschool children demonstrated a somewhat higher rate of distinctly fewer chews per bite. Boys showed increasing chew rates with increasing age. Talk rates also increased with age but were unrelated to sex or weight status. Sip rates were not significantly associated with age, sex, or weight status. These results support the hypothesis that overweight persons are characterized by an increased eating rate and show that it is apparent even around the time of first self-feeding. 相似文献
986.
The development of the intention to communicate was examined by attempting to identify the point at which prelinguistic vocalizations are used by infants as a means of communication. This achievement was related to the infants' cognitive development. It was hypothesized that Piagetian stage 5 in the development of causality may be a prerequisite for the intentional use of vocalizations. 46 infants (X age = 10.7 months, range: 8 months--14.3 months) and their mothers were videotaped in a structured, naturalistic setting. 2 "frustration" episodes were devised to encourage communication, and the infants' vocalizations as well as other behaviors were coded by 2 observers. 2 Piagetian tasks were selected to assess the causal developmental level of the child. A significant relationship between causal developmental level and the occurrence of intentional vocalizations was found. The results support the hypothesis that stage 5 causal development may be a prerequisite to the use of intentional vocalizations. 相似文献
987.
K. G. Saw Omar Majid N. Abdul Ghani H. Atan R. M. Idrus Z. A. Rahman K. E. Tan 《British journal of educational technology : journal of the Council for Educational Technology》2008,39(3):475-485
This paper is a study on the interaction patterns of distance learners enrolled in the Mathematics and Physics programmes of Universiti Sains Malaysia in the videoconferencing learning environment (VCLE). Interaction patterns are analysed in six randomly chosen videoconferencing sessions within one academic year. The findings show there are more interactions in the graphics display mode than the video display mode. The graphics display mode, which involves the simultaneous interaction of the teacher, students and course materials, shows greater student engagement in the VCLE. The focus on a three-component interaction in distance learning differs from previous studies which looked at distinct types of two-component interactions. The types of communicative interaction, in particular the explanatory and cognitive types which are dominant in the graphics display mode, are discussed within the construct of learning. The higher number of teacher-initiated interactions may also imply that the teacher plays a crucial role in creating and maintaining a community of inquiry focused on exploring and developing content as well as giving feedback on concepts, ideas or solutions. 相似文献
988.
Michael G. Levykh 《Educational theory》2008,58(1):83-101
A bstract . Many recent articles, research papers, and conference presentations about Lev Vygotsky's zone of proximal development (ZPD) emphasize the "extended" version of the ZPD that reflects human emotions and desires. In this essay, Michael G. Levykh expands on the extant literature on the ZPD through developing several new ideas. First, he maintains that there is no need to expand ZPD to include emotions, as its more "conservative" dimensions (cognitive, social, cultural, and historical) already encompass affective features. Second, Levykh emphasizes that an emotionally positive collaboration between teachers and students in a caring and nurturing environment must be created from the outset. Finally, he asserts that culturally developed emotions must mediate successful establishment and maintenance of the ZPD in order to be effective. According to Levykh, Vygotsky's notion that learning can lead development represents a crucial contribution to our understanding of teaching and learning by clearly showing that emotions are vital to human learning and development. 相似文献
989.
Okhee Lee Jaime Maerten‐Rivera Randall D. Penfield Kathryn LeRoy Walter G. Secada 《科学教学研究杂志》2008,45(1):31-52
This study is part of a 5‐year professional development intervention aimed at improving science and literacy achievement of English language learners (or ELL students) in urban elementary schools within an environment increasingly driven by high‐stakes testing and accountability. Specifically, the study examined science achievement at the end of the first‐year implementation of the professional development intervention that consisted of curriculum units and teacher workshops. The study involved 1,134 third‐grade students at seven treatment schools and 966 third‐grade students at eight comparison schools. The results led to three main findings. First, treatment students displayed a statistically significant increase in science achievement. Second, there was no statistically significant difference in achievement gains between students at English to Speakers of Other Language (ESOL) levels 1 to 4 and students who had exited from ESOL or never been in ESOL. Similarly, there was no significant difference in achievement gains between students who had been retained on the basis of statewide reading test scores and students who had never been retained. Third, treatment students showed a higher score on a statewide mathematics test, particularly on the measurement strand emphasized in the intervention, than comparison students. The results indicate that through our professional development intervention, ELL students and others in the intervention learned to think and reason scientifically while also performing well on high‐stakes testing. © 2007 Wiley Periodicals, Inc. J Res Sci Teach 45: 31–52, 2008 相似文献
990.
Brian Byrne William L. Coventry Richard K. Olson Jacqueline Hulslander Sally Wadsworth John C. DeFries Robin Corley Erik G. Willcutt Stefan Samuelsson 《Journal of Research in Reading》2008,31(1):8-21
As part of a longitudinal twin study of literacy and language, we conducted a behaviour‐genetic analysis of orthographic learning, spelling and decoding in Grade 2 children (225 identical and 214 fraternal twin pairs) in the United States and Australia. Each variable showed significant genetic and unique environment influences. Multivariate analyses revealed very high genetic correlations among the variables, indicating that the same genes are involved in their aetiology. These genes are partly independent of those contributing to intelligence. A further analysis indicated that the covariation between decoding and orthographic learning is mediated by shared genes rather than by a direct causal path. The authors argue that a learning parameter, most directly assessed by orthographic learning in this study, underlies all three literacy variables. The results are also discussed in relation to Share's self‐teaching hypothesis, which may require modification. 相似文献