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981.
982.
This is a survey of the prevalence of weight reducing and weight gaining in high school children. Our sample of 1,373 high school girls and boys was geographically, racially, and economically diverse. On the day of the survey, 63% of the girls and 16.2% of the boys reported being on weight reducing regimens; 9.1% of the girls and 28.4% of the boys were trying to gain weight. Most female reducers and male gainers were already normal weight. Compared to other racial groups, whites and Hispanics were more likely to be reducing, whereas blacks were more likely to be gaining. Exercise and moderate caloric reduction were most popular for weight reducing, and a small but significant number were regularly using fasting, vomiting, laxatives, and appetite suppressants. The direction of weight modification for girls and boys conformed to stereotyped physical ideals. The rate of weight reducing in female high school adolescents has increased significantly since similar surveys of American youths 20 years ago.  相似文献   
983.
Cognitive maps as orienting schemata   总被引:3,自引:0,他引:3  
A "point-to-unseen-targets" task was used to test two theories about the nature of cognitive mapping. The hypothesis that a cognitive map is like a "picture in the head" predicts that (a) the cognitive map should have a preferred orientation and (b) all coded locations should be equally available. These predictions were confirmed in Experiments 1 and 3 when targets were cities in the northeastern United States and learning was from a map. The theory that a cognitive map is an orienting schema predicts that the cognitive map should have no preferred orientation and that targets in front of the body should be localized faster than targets behind the body. These predictions were confirmed in Experiments 1 and 2 when targets were local landmarks that had been learned via direct experience. In Experiment 3, when cities in the Northeast were targets and geographical knowledge had been acquired, in part, by traveling in the Northeast, the observed latency profiles were not as predicted by either theory of cognitive mapping. The results suggest that orienting schemata direct orientation with respect to local environments, but that orientation with respect to large geographical regions is supported by a different type of cognitive structure.  相似文献   
984.
985.
This study examines the effect of different behavioral conditions on patterns of correlation between regional cerebral metabolic rates for glucose. Cerebral glucose metabolism was determined with positron emission tomography and (11C)-deoxyglucose in 29 normal subjects between the ages of 23 and 55. Seventeen subjects were studied in an unstimulated (resting) condition and 12 subjects during a phoneme monitoring language stimulation. Partial correlation coefficients, controlling for whole brain glucose metabolism, were calculated for pairs of metabolic rates in 14 cortical and 2 subcortical regions. Both stimulated and unstimulated subjects showed statistically significant correlations between left and right hemisphere homologs. The stimulated subjects also showed significant within-hemisphere correlations between left but not right hemisphere regions. These included left perisylvian regions classically associated with language functions (left inferior frontal, left superior temporal and left transverse temporal cortical regions) as well as other regions. Significant correlations between left regions and a right superior temporal region were also found. In general, these findings show a pattern of cross-hemisphere symmetry at rest and of hemisphere asymmetry during stimulation. Moreover, the asymmetry observed during stimulation appears to be superimposed upon a pattern of cross-hemisphere symmetry similar to that observed in the unstimulated state.  相似文献   
986.
When sighted persons try to identify one of two speech utterances coming from different directions, they display both a frontal position advantage, i.e., better recognition of inputs from the front than of those from the rear, and a right-side advantage, better recognition of inputs from the right than of those from the left. The present study demonstrates a dissociation of the two effects in blind subjects (N = 10) who showed no frontal position advantage together with a right-side advantage superior to that of control sighted subjects (N = 16). There was no systematic difference between congenitally blind subjects and noncongenitals. The absence of frontal position advantage in the blind is consistent with the notion that this effect originates in the habit of sighted listeners to orient toward the source of heard speech. The occurrence of at least normal right-side advantage in the blind does not support recent suggestions of reduced lateralization of language functions in such subjects.  相似文献   
987.
One of the possible adaptive costs of coping with stress is diminished capacity to respond to subsequent adaptive demands. This paper examined the complex interplay between major life events and one source of chronic strain. Residents of the greater Los Angeles metropolitan area exposed to higher levels of smog, who had also experienced a recent stressful life event, exhibited poorer mental health than those exposed to pollution who had not experienced a recent stressful life event. There were, however, no direct effects of smog levels on mental health. These patterns of results were replicated in both a cross-sectional and a longitudinal study. The interplay of psychosocial vulnerability and environmental conditions is discussed.  相似文献   
988.
This project examined psychosocial characteristics of 24 preschool-aged siblings of handicapped children in relation to a control group of 22 siblings of nonhandicapped children. Subjects were matched on family size and income, sibling age, birth order, sex, age spacing, and marital status of their parents. Results indicated no statistically significant differences between groups of children on measures of perceived self-competence and acceptance, understanding of developmental disabilities, empathy, and child care responsibility. Significant group differences were found where brothers of handicapped children were rated by their mothers as being more depressed and aggressive than brothers of nonhandicapped control children. Sisters of handicapped children were rated by mothers as being more aggressive than sisters of nonhandicapped children. Sisters of handicapped children and brothers of nonhandicapped children had significantly fewer privileges and more restrictions on their home activities than other groups. Results are discussed in relation to previous research on older silbings of handicapped children and the general literature on family stress and childhood disability and disease. The importance of examining sibling functioning via multiple measures of child behavior is stressed.The authors are grateful to the children and families who participated in the project. The assistance of Dr. Ricardo Barrera, Christine DiBlasio, Lisa Kaye, Paola Bellabarba, Jeanne Logozzo, Donna Motley, Jennifer Harter, and Tina Meisell is also gratefully acknowleged. This project was funded by Grant Number G008300345 from the U.S. Department of Education.  相似文献   
989.
The purpose of this paper is to present a new electromagnetic device which uses alternating magnetic fields for tracking movements of multiple points inside and outside the vocal tract. It is biologically safe, noninvasive, it does not interfere with speech movements, allows for multiple recording in the same subject, and for easy collection of large amounts of data. It is especially suitable for evaluation of patients with speech motor impairments.  相似文献   
990.
Common formulations of the principle of charity in translation seem to undermine attributions of irrationality in social scientific accounts that are otherwise unexceptionable. This I call the problem of irrationality. Here I resolve the problem of irrationality by developing two complementary views of the principle of charity. First, I develop the view (ill-developed in the literature at present) that the principle of charity is preparatory, being needed in the construction of provisional first-approximation translation manuals. These serve as the basis for explanatory accounts and associated refinements in the translation manual. In developing such explanatory accounts, the principle of charity is no longer constraining. Thus, the principle of charity applies only in the early stages of constructing translation manuals, and there is no problem of irrationality in the later stages of constructing translation manuals. Second, I reduce the principle of charity, where it does apply, to a special case of what I call the principle of explicability: so translate as to attribute explicable beliefs and practices to the speakers of the source-language. I show that the appropriate formulation of the principle of charity counsels just what the principle of explicability requires in the early stages of social scientific investigation.I am grateful to Robert Barrett, Roger Gibson, and Paul Roth for their generous assistance.  相似文献   
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