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1.
Rats (Rattus norvegicus) that received a taste cue (saccharin, saline, quinine, or sucrose) paired with a lithium chloride (LiCl) injection displayed a robust decrease in consumption of that taste, relative to controls that had the taste unpaired with LiCl. Consumption of the paired taste increased with each nonreinforced presentation (i.e., extinction). After asymptotic extinction, rats that had had a 0.1% saccharin cue paired with LiCl consumed less of the saccharin solution than did controls. A similar data pattern was observed with a 10% sucrose solution. These results are consistent with the view that some aspect of the excitatory CS-US association remains after extinction. On the other hand, rats that had a bitter (0.005% or 0.001% quinine) or salty (1% or 0.5% saline) solution paired with LiCl drank similar amounts of the fluid as controls after asymptotic extinction treatment. Together, these experiments suggest that a taste that is either sweet or preferred is required in order to demonstrate the chronic decrease in fluid consumption after extinction treatment. The data suggest that the conditioning experience prevents the later development of a preference for the sweet taste, rather than there being a retained aversion that suppresses fluid consumption.  相似文献   

2.
The retention and extinction of a conditioned taste aversion after either short (6-day) or long (60-day) intervals was investigated in preweanling (18-day-old) and adult rats. Taste-only and illness-only control conditions were employed, as were variations in the concentration of the US (holding LiCl amount constant). Results indicated that after the short retention interval, retention of the taste aversion was equivalent for both ages. After the long interval, however, the 18-day-old rats exhibited significantly weaker taste aversion than their adult counterparts— infantile amnesia. Manipulation of US concentration had no effect on the magnitude of the taste aversions for either age or retention interval. The results are discussed in terms of their implications for infantile amnesia and general laws of learning.  相似文献   

3.
Latent inhibition of conditioned taste aversion (CTA) is sensitive to changes in the temporal context. A change in the time of day of conditioning with respect to the time of day of the preexposure can disrupt the latent inhibition. This contextual change in the time of day may reveal a temporal specificity of latent inhibition. The optimum procedure to induce this temporal specificity is not well established. For example, it has been shown that a long period of habituation to temporal contexts is one factor that can determine the effect. However, the experimental conditions on the conditioning day that facilitate this phenomenon are unknown. The aim of this study is to elucidate whether a restriction in the intake of the conditioned taste stimulus affects the temporal specificity of latent inhibition. Two main groups of Wistar rats were tested in a latent inhibition of CTA paradigm, in which the temporal specificity of this phenomenon was analyzed by a change in the time of day of conditioning. The intake of the taste stimulus was restricted in the conditioning day in one of the groups, but this restriction was not applied in the other group. The results indicated temporal specificity of latent inhibition only in the group without restriction, but not in the group with limitation in the intake of the taste stimulus during conditioning. These findings can help to elucidate the characteristics of the procedure to induce temporal specificity of latent inhibition.  相似文献   

4.
Adult rats were injected with lithium chloride (LiCl) after consumption of a novel flavor (chocolate milk) that either was or was not presented together with a novel ambient odor (banana) as a compound conditioned stimulus (CS). In Experiment 1, the adults’ consumption of the flavor 24 h after conditioning was compared with that of weanling rats given the same conditioning treatment on Postnatal Day 21. The results confirmed previous indications that the reduction in aversion observed for adults conditioned with the compound CS (overshadowing) was weak or nonexistent in weanlings. After a longer retention interval (21 days), there was no evidence of overshadowing in adults despite maintained retention of the basic conditioned aversion. In Experiment 2 this decrease in overshadowing after a long retention interval was replicated with adult animals and extended to a different method of testing. The form of the effect was the same as in Experiment 1: The decrease in overshadowing occurred over the retention interval without loss in retention of the basic taste aversion; the decrease in overshadowing was a consequence of anincrease in the flavor aversion displayed by animals conditioned with the compound CS. The impaired flavor aversion (i.e., the overshadowing) observed shortly after conditioning apparently was due to factors associated with memory retrieval, rather than to reduced attentional or associative strength.  相似文献   

5.
Rats were successively exposed to three solutions with distinctively different flavors and then tested for both neophobia and propensity to form conditioned taste aversions to a fourth distinctively flavored solution. All permutations between the four solutions (salty, bitter, sweet, and sour) were examined. The prior exposures resulted in attenuation of neophobia to novel salty and sour solutions, but not to equally novel bitter or sweet solutions. These effects were found to depend upon thediversity of the prior ingestive events rather than upon either a single specific flavor experience or a summation of the reductions in generalized neophobia accrued by each substance separately; both of the latter findings are inconsistent with stimulus generalization being responsible for the observed attenuation of neophobia to salty and sour solutions following exposure to diverse different solutions. A further test of generalization between the salty and bitter solutions, consisting of associating one flavor with poison and extinguishing the avoidance response in half the animals prior to testing for generalization of conditioned taste aversion to the other flavor, also proved negative. Although these effects of exposure to flavors distinctly different from the test solution may be dependent upon solution concentrations, further research found that the same pretest exposures and same test concentrations failed to inhibit formation of conditioned taste aversions. A demonstration of “latent inhibition” attested to the sensitivity of our procedure to potential interference with acquisition of conditioned taste aversions. The results are considered in light of the relationship between neophobia and conditioned tasted aversions, the differential biological relevancy of specific tastes, and abstraction as a cognitive capability of rats. The possibility is raised that the defense against toxins is not the primary function of neophobia.  相似文献   

6.
7.
Internationalization has become intertwined with efforts for institutions to compensate for declines in public funding with the development of new revenue streams. The purpose of this study is to understand the social construction of entrepreneurship in internationalization in the United States as well as explore the multiple meanings of entrepreneurship and its contradictions in discourse among senior international officers. The findings discuss and explore competing views, tensions and ethical complexities of the ‘new entrepreneurism’ increasingly common in internationalization, which blends creative problem-solving with pressures for revenue generation. The findings of this study illustrate that as the world faces genuine existential crises that threaten the continued existence of our species on the planet, internationalization is in the midst of an identity crisis. The drift towards privatization is proving to be increasingly unsustainable and an entirely insufficient response to the existential threats that face the world.  相似文献   

8.
The effects of select drugs, dosages, and modes of administration upon learned taste aversions were compared among groups of wild-caught male and female Philippine rice rats (R. r. mindanensis). Experiment 1 compared two-choice saccharin aversions for 28 days among groups intubated with copper sulfate, cyclophosphamide, lithium chloride, red squill, sodium chloride (control), or deionized water (control). Main results were that 375 mg/kg lithium chloride produced the greatest sustained aversions, whereas 198 mg/kg cyclophosphamide and 210 mg/kg red squill produced moderate aversions, with males showing more resistance to extinction than females. Experiment 2 compared saccharin aversion among matched groups of male and female rats that received low (36 mg/kg), moderate (105 mg/kg), or high (368 mg/kg) dosages of lithium by gavage, ip injection, or ingestion. Sex differences in rates of extinction were found for the ingestion and injection-dosed rats, but no sex difference was again found for rats dosed by gavage. A significant mode × day interaction indicated that extinction progressed more rapidly for rats dosed by gavage. For all modes of administration, high dosages yielded intense 28-day aversion, moderate dosages produced intermediate 3–5 day aversion, and low dosages caused no aversion.  相似文献   

9.
This paper focuses on the use of images to promote reflection and analysis of inclusive practices. The image-based work was set in the context of a two-year action research study, which took place in Tanzania and Zambia, 2001–2003, in collaboration with researchers from the Enabling Education Network (EENET), based at the University of Manchester's School of Education. This study, entitled, 'Understanding Community Initiatives to Improve Access to Education' involved the use of a wide range of processes to promote reflection, analysis and documentation, including a range of different types of images. We reflect here on the learning, which took place among the researchers in all three countries in using images as a basis for reflection on inclusive education.  相似文献   

10.
Abstract

Integrating climate change into environmental education programs and formal science classrooms can be difficult, as the issue remains controversial and highly politicized among the American public. This study proposes that the same cultural values that shape worldview differences and divide public opinion on anthropogenic climate change will influence if and how science educators support education on the topic. An online survey with quantitative and qualitative measures was distributed among science educators in the southeastern United States to test what, if any, impact cultural cognition has on their opinions about climate change education. The results suggest that respondents’ cultural values have a significant influence on their intentions to support climate change education and preferences for curricula content. The findings also suggest potential avenues for the field of environmental education to develop climate change materials that may help decrease unintentional biases among science educators and more effectively engage their support in teaching its causes and potential solutions regardless of worldview differences.  相似文献   

11.
12.
During simultaneous discrimination training, there is evidence that some of the value of the S+ transfers to the S?. When the value of the S+ is altered outside the context of the simultaneous discrimination, two very different predictions are made concerning its effect on its S?, depending on whether one views the S+ as an occasion setter or as a stimulus capable of transferring value. In four experiments, pigeons were trained with two similar simultaneous discriminations, A+B? and C+D?, and two single-stimulus trial types, A and C, (in which A always had greater nominal value than C). According to value transfer theory, on test trials, B should always be preferred over D, because B and D should be affected by the net values of A and C, respectively. According to an occasion setting account, however, D should be preferred over B because the presence of D signals a higher probability of reinforcement for responding to C than when C is alone, and/or the presence of B signals a lower probability of reinforcement for responding to A than when A is alone. In all four experiments, the pigeons preferred B over D, a result consistent with value transfer theory. Thus, an S? can acquire value from an S+ even when that value is conditioned in a “context” different from that of the simultaneous discrimination.  相似文献   

13.
Developmental changes were examined in the associations among physical and relational aggression, and sociometric and perceived popularity based on peer nominations. Participating in the longitudinal study were 905 children (440 girls, 465 boys) from ages 10 to 14. Associations between the forms of status and between the forms of aggression decreased over time. Relational aggression increasingly predicted high social prominence but low social preference; physical aggression was increasingly less disliked but decreasingly predictive of prominence. The effect of relational aggression on perceived popularity was strong for girls. Perceived popularity preceded physical and relational aggression for both genders. Implications for the attainment of high status, processes of peer influence on antisocial behavior, and gender differences in the meaning of status are discussed.  相似文献   

14.
Although homework is generally believed to be an important supplement to in-school learning, research has not yet fully clarified the relationship between homework and achievement. This cross-cultural study analyzed the relationship between homework time and mathematics achievement drawing on data from 231,759 students in 9,791 schools and 40 countries who participated in the Programme for International Student Assessment (PISA) 2003. Multilevel analyses found a positive association between school-average homework time and mathematics achievement in almost all countries, but the size of the association decreased considerably once socioeconomic background and school track were controlled. At the student level, no clear-cut relationship was established between homework time and achievement across the 40 countries. The results highlight the need to use multilevel analyses and to control for confounding variables in homework research.  相似文献   

15.
The purpose of this integrative literature review was to draw together recognised streams of knowledge to inform contemporary leadership of school systems in democratic societies. The article integrates scholarship in ethical leadership (EL) and social justice leadership (SJL). The resultant conceptualised model is an expanded version of a preliminary model included in a research brief of an empirical study. The Ethical Leadership Praxis in a Global Society model includes four interactive dimensions: (1) understanding social justice theory and leadership theory, (2) applying state, national and professional ethical/legal standards, (3) engaging in ethical leadership practice and role modelling for culturally responsive leadership (CRL), and (4) employing personal leadership ethics and core values as a cyclical process of self-reflection and decision-making. This article makes an original contribution for building leadership praxis centred on ethical leadership. The model applies ethical and social justice leadership theory and encourages leaders to self-reflect on their own values, practices of leadership and how their actions can create inclusivity. Empirical studies testing the model is recommended in a variety of international educational settings.  相似文献   

16.
Experiment 1 involved the use of plastic and wooden objects and trial-unique problems. The rats performed successfully on nonconceptual oddity problems given before and after conceptual training, showing that the testing conditions were suitable, but they showed chance performances on the trial-unique problems. Experiment 2 involved the use of olfactory discriminanda. Five pretraining problems and 300 unique five-trial problems were presented. Two of 3 rats performed better than chance on Trial 2 and on Trials 3–5, but all performed at chance levels on Trial 1 throughout. The data suggest that the rats responded to specific odors on Trials 2–5 following the Trial 1 experience, as opposed to respondingconceptually to the “odd” odor. Had they responded conceptually to odd odors, they should have performed better than chance on Trial 1. These findings and the general logical argument that they support are considered in the context of the numerous inconclusive reports of the use of the oddity concept by nonprimate animals.  相似文献   

17.
England has experienced recent growth in the prevalence of private tutoring (PT). The qualitative study reported in this article aims to explore the perceptions of 14 Year 6 pupils and their teachers from three state-maintained primary schools in East Kent on PT participation and its impact on grammar school admissions. Data were collected through individual and focus group interviews and pupils' drawings. The data revealed that teachers were not totally aware of the scale of PT in their classes and ascribed PT merely to parental decision to prepare their child to pass the 11-plus, grammar school entrance test. However, some pupils indicated that they shared in the decision to have PT, affirming that it was not only for 11-plus test familiarisation and practice. PT also contributed to greater pupil confidence, involvement and enthusiasm for learning, together with improvement in social interactive skills (i.e. intangible benefits). Both teachers and pupils also explained the disadvantages of PT, including the psychological and financial burdens on the whole family and changing the playing field level. Teachers proposed some solutions to help Year 6 pupils without PT. From this qualitative study, pedagogical implications as well as areas for ongoing research are suggested.  相似文献   

18.
Imbalanced allocation of teacher resources is a major factor causing inequality in K-12 education in China. Traditional ways to solve this problem, such as on-site support teaching and recorded lectures of quality teachers, have posed many defects. It is suggested that information and communication technology should be employed to deal with the problem. The research put forward an idea of building a particular real-time video conferencing environment (RVCE) for support teaching guided by the Community of Inquiry framework. An experimental environment was built in June 2014, which comprised two Internet-connected multimedia classrooms, one as the local room and the other as the remote room. A case study was then conducted to examine the efficacy of RVCE. Results showed that RVCE could support different kinds of learning activities and would be a feasible practice to promote the Equality of K-12 Education in China.  相似文献   

19.
European Journal of Psychology of Education - The grades of students have been shown to severely decrease during the transition from high school to university. Although past findings have shown...  相似文献   

20.
In this response, we attempt to clarify our position on conceptual change, state our position on mental models being a viable construct to represent learning, indicate important issues from the social cultural perspective that can inform our work on conceptual change and lastly comment on issues that we consider to be straw men. Above all we argue that there is no best theory of teaching and learning and argue for a multiple perspective approach to understanding science teaching and learning.
Reinders DuitEmail:

David F. Treagust   is a professor of science education at Curtin University of Technology in Perth, Western Australia where he teaches courses in campus-based and international programs related to teaching and learning science. His research interests include understanding students’ ideas about science concepts and how these ideas relate to conceptual change, the design of curricula and teachers’ classroom practices. Reinders Duit   is a professor of physics education at the Leibniz Institute for Science Education (IPN) at the University of Kiel, the Central Institute for Science Education Research in Germany. A major concern of his work has been teaching and learning science from conceptual change perspectives. More recently, his work includes video-based studies on the practice of science instruction as well as teacher professional development.  相似文献   

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