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An invisible displacement test was administered to cats in order to test the hypothesis that search behaviour in this species is influenced by their limited capacity for object permanence as well as by their previous experience with the environment. Experiment 1 compared three groups of cats in a five-choice hiding task in which the hiding places could be discriminated by their spatial positions. Two groups received a visible displacement training before the invisible displacement test and one group did not. Experiment 2 compared two groups of trained subjects in the same task, but the hiding places could be discriminated by spatial and visual cues. The results confirmed that cats are unable to solve problems with invisible displacements. The visible displacement training improved their performance, but was not sufficient to make them succeed. Experience with the hiding potential of the covers also gives more persistence to search behaviour. Finally, the distribution of search attempts is not determined by the proximity to the target and is influenced only partially by the subjects' previous experience. Like Stage 5 infants, cats rely mainly on their immediate perception. They search for an object in the last location they have seen it disappear or under the nearest cover from this location.  相似文献   
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Tested a 7-month, media-based, community intervention among Hispanics in San Francisco designed to change levels of information on the damaging effects of cigarette smoking and on the availability of culturally appropriate cessation services. Three community-wide surveys of Hispanics were conducted with independent random samples, two as baselines (n = 1,660 and 2,053) and one postintervention (n = 1,965). Results showed that changes in the level of awareness of cessation services had taken place after implementation of the intervention. Furthermore, those changes took place primarily among the less acculturated Spanish-speaking Hispanics who were the target of the intervention. The changes in information reported here demonstrate that a culturally appropriate information dissemination campaign that utilizes multiple channels can produce changes in a community's level of information even when the campaign is implemented for a relatively short period.  相似文献   
64.
How is meaning assigned to those terms in a theory which are remote from direct observational instantiation? Models and analogies play a role, but close examination of theories in high energy physics shows that the design of experimental apparatus also influences the interpretation of such terms. Certain apparatus favours certain kinds of effects, and this affects the way mathematical theories are interpreted. In particular track producing apparatus becomes involved with theories in which photonic terms are picked out in the theory. A further conceptual constraint is thus introduced. It is argued that this situation favours the interpretation of dispositional properties as affordances rather than as simple dispositions.  相似文献   
65.
The role accorded to the public by scientists and philosophers of science has undergone an essential historical change in the last three centuries. Public participation in (witnessing of) scientific experiments was considered an important requirement for 17th century experimenters (e.g. for Boyle or Pascal). The cognitive role played by lay persons was later substantially downgraded; witnessing went out of fashion, while science became more and more esoteric and a matter for experts only. Part of this process was that all scientific disciplines became intensively compartmentalized and in consequence a rather puzzling or even paradoxical situation appeared: that the scientists themselves were and are being reduced epistemically to the status of lay persons, outside of their proper field of expertise (as was pointed out by J. Hardwig). The paper deals with some cognitive aspects of this historical process.  相似文献   
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This paper describes a research program on mentally retarded parents and their children. For this nation-wide study, two structured questionnaires were sent to all municipalities in Norway. Both questionnaires were sent to public health nurses and were followed-up by a structured telephone interview based on the questionnaires. The primary aim of the study was to survey the number of children born to mentally retarded parents. In addition, the children's needs and functional abilities were to be assessed. Twenty-three mentally retarded persons had given birth in the course of the past twelve months. A total of 126 children with mentally retarded parents were identified, with an incidence of 27 children per year, and a prevalence of approximately 430 children under 16 years of age in a population of 4 mill. People with a mean of 1.05 child per family. About 43% of the children of mentally retarded parents appeared to have learning difficulties. Forty percent of the children suffered from failures of care. Between 25% and 68% of the children with learning problems had poorly developed motor or language abilities, sense modalities or psycho-social status.  相似文献   
68.
The aim of this study was to examine two hypotheses derived from theoretical models of the role of learning and performance goals in cognitive functioning. The first predicts that being highly focused on performance goals leads students to develop lower levels of self-efficacy than those who are less focused on performance. The second hypothesis predicts that the combination of high performance goals and low self-efficacy will have a negative impact on students' self-regulation and performance in a new task. After having filled out a questionnaire assessing their goals, 128 female students were met individually and asked to solve a verbal concept formation task. Self-efficacy was assessed prior to the resolution of the task during which self-regulation and performance were observed. Contrary to the first hypothesis, students having high performance goals were found to have higher self-efficacy than those having low goals. In addition, no interaction between self-efficacy and performance goals was found on self-regulation and performance on the task. The results showed that whatever students' goals, self-efficacy is a powerful determinant of self-regulation and performance. The discussion emphasizes the role of self-efficacy and the value of a motivational profile combining high concern for both performance and learning goals in cognitive functioning.  相似文献   
69.
The first part of this paper proposes a continuum of ideological premises that seeks to account for the broad range of immigrant integration policies adopted by Western democratic states. In the second part, a review of Social Psychological models of immigrant acculturation strategies demonstrates the need to explain more clearly the interactive nature of immigrant and host community relations. The Interactive Acculturation Model (IAM) presented next proposes that relational outcomes are the product of the acculturation orientations of both the host majority and immigrant groups as influenced by state integration policies. The model makes predictions regarding the acculturation combinations most likely to produce consensual, problematic, and conflictual relational outcomes between immigrants and members of the host community. Social psychological research is needed to test the validity of the IAM model empirically.  相似文献   
70.
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