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871.
This study replicated the results of an earlier one in which college women showing psychological similarities to anorexics indicated an unrealistically larger body-image relative to controls but only if they were relatively thin. This kind of perceptual enhancement was not found when inanimate objects were rated. The proposal that an enhanced body image plays a dynamic role in motivating food restraint (and may increase the risk of becoming anorexic) was supported by an analysis of dieting strategies. 相似文献
872.
B S Randhawa 《Psychological reports》1990,66(2):531-538
The present study investigated the congruence between the factor structures of the learning environment and cognitive variables for mathematics and English courses in Grade 10. Three common factors were obtained in each course. Procedural characteristics and cognitive factors in mathematics were highly similar to the corresponding factors in English. However, the formative characteristics factor identified in mathematics was not congruent to the corresponding factor in English. Learning environment variables produced two factors. These factors resembled the congruent factor properties for the two courses when the learning environment and cognitive variables were factor analyzed together. Implications for learning and instructional research are mentioned. 相似文献
873.
The Slade model for development of anorexia nervosa proposes that the female may seek success and control in her life by pursuing a thin body through dieting when faced with serious personal problems. Extending upon this model, the present program of research has sought to identify those characteristics of women generally at-risk for anorexia nervosa that would make dieting behavior especially successful, permitting the progression from food restraint into food aversion. The present studies considered whether heightened and stress-related inner stimulation could interfere with the at-risk woman's sensitivity to hunger sensations, thereby decreasing her motivation to eat. A series of analyses conducted within two studies indicated: (1) a relationship between elevated daily stress, concern over being over-whelmed by inner feelings, and a loss of discrimination regarding sources of inner feelings, (2) a tendency to narrow attentional focus when overloaded with excessive internal stimulation, and (3) diminished sensitivity to hunger sensations for women generally at-risk for anorexia nervosa given a narrowed attentional focus. 相似文献
874.
The author is an internist in a non-university hospital. He discusses the possibilities and limits of dealing with patients suffering from ulcerative colitis and Crohn's disease. He demonstrates the clinical importance of a psychoanalytic perspective with three case illustrations. 相似文献
875.
876.
877.
Arthur B. Millman 《Synthese》1990,82(1):23-52
This paper is a detailed critical study of Adolf Grünbaum's work on the Duhemian thesis. I show that (a) Grünbaum's geometrical counterexample to the (D1) subthesis is unsuccessful, even with minimal claims made for what the counterexample is supposed to show, and (b) the (D2) subthesis is not a reasonable one (and cannot correctly be attributed to Duhem). The paper concludes with an argument about the relation between the Duhemian thesis, concerning component hypotheses of a scientific theory, and the view that it is impossible to falsify entire theories conclusively. 相似文献
878.
Rodger Beehler 《Studies in Philosophy and Education》1990,10(4):315-335
The essay examines the argument advanced by E.D. Hirsch, Jr., for instituting ‘cultural literacy’ as a fundamental priority of schools. A number of confusions and equivocations in Hirsch's reasoning are identified, and the propensity of his project to indoctrinate is exposed. Among the features of Hirsch's argument shown to be troubling are his shifting construal of ‘language’, his inconsistency about the requirements of cultural literacy, and his uncritical relation to traditional images of the American past and present. The upshot is to raise the question why Hirsch's project has elicited wide support and praise. 相似文献
879.
Michael A. Arbib 《Synthese》1990,84(1):43-58
In this paper, we offer a Piagetian perspective on the construction of the logico-mathematical schemas which embody our knowledge of logic and mathematics. Logico-mathematical entities are tied to the subject's activities, yet are so constructed by reflective abstraction that they result from sensorimotor experience only via the construction of intermediate schemas of increasing abstraction. The ‘axiom set’ does not exhaust the cognitive structure (schema network) which the mathematician thus acquires. We thus view ‘truth’ not as something to be defined within the closed ‘world’ of a formal system but rather in terms of the schema network within which the formal system is embedded. We differ from Piaget in that we see mathematical knowledge as based on social processes of mutual verification which provide an external drive to any ‘necessary dynamic’ of reflective abstraction within the individual. From this perspective, we argue that axiom schemas tied to a preferred interpretation may provide a necessary intermediate stage of reflective abstraction en route to acquisition of the ability to use formal systems in abstracto. 相似文献
880.
Converging operations on a basic level in event taxonomies 总被引:1,自引:0,他引:1
Research on object concepts has identified one level of abstraction as "basic" in cognition and communication. We investigated whether concepts for routine social events have a basic level by replicating the converging operations used to investigate object concepts. In Experiment 1, subjects were presented with event names from a taxonomy and were asked to list the actions comprising the event. Many more actions were listed at the middle than at the highest taxonomic level, without a further increase at the most specific level, paralleling the pattern of superordinate-, basic-, and subordinate-level object concepts. From these action lists, brief stories were composed for each event. In Experiment 2, subjects made pairwise similarity judgments on the stories. The mean similarity of events increased with specificity, as expected. But differentiation of categories (within-category similarity compared to between-category similarity) was highest for super-ordinates, contrary to results with object categories. In Experiment 3, subjects were fastest in recognizing actions as belonging to events named at the basic level. In Experiment 4, subjects predominantly chose basic-level terms to name stories. We conclude that event taxonomies do show basic-level structure, albeit a less sharply defined and less stable structure than in object taxonomies. The benefits and hazards of extending models of object concepts to other entities, such as social events, are discussed. 相似文献