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911.
There are many conditions in which identification proceeds faster for the global form of a hierarchical pattern than for its local parts. Since the global form usually contains more lower spatial frequencies than do the local forms, it has frequently been suggested that the higher transmission rate of low spatial frequencies is responsible for the global advantage. There are also functional hemispheric differences. While the right hemisphere is better at processing global information, the left hemisphere has an advantage with respect to local information. In accordance with the spatial-frequency hypothesis, it has been speculated that this difference is due to a differential capacity of the hemispheres for processing low and high spatial frequencies. To test whether low spatial frequencies were responsible for the global advantage and/or for the observed hemispheric differences, two experiments were carried out with unfiltered and highpass-filtered compound-letter stimuli presented at the left, right, or center visual field. The first experiment, in which the target level was randomized in each trial block, revealed that low spatial frequencies were not necessary for either global advantage or for hemispheric differences. Highpass filtering merely increased the response times. In the second experiment, the target level was held constant in each block. This generally increased the speed of responding and produced interactions between filtering and global-local processing. It was concluded that both sensory and attentional or control mechanisms were responsible for global precedence and that the hemispheres differed with respect to the latter.  相似文献   
912.
A total of 229 late adolescents (a large majority 15 to 19 years of age) completed a questionnaire that assesses a broad range of videogame-relevant experiences, preferences, and attitudes. Videogame playing was found to be a more popular, and a more highly regarded, activity among males than females. Gender differences were also found in participants' ratings of their motivations for playing videogames, their evaluations of particular characteristics of videogames, and their selection of their “most favorite” videogame. The differences between frequent and infrequent videogame players appeared to be limited to differences in the extent to which videogame playing is pursued and evaluated as a positive leisure activity, rather than reflecting broad differences in interest or personality. Some relations were found between participants' self-reported personality characteristics (i.e., self-esteem, empathy, conscientiousness, and introversion) and their attitudes toward videogames.  相似文献   
913.
The present study uses attribution theory to identify factors that may lead to unfavorable emotional reactions toward patients with schizophrenia and to highlight factors that may contribute to the observed inverse relationship between industrial status of a country and schizophrenia outcome. University students from Mexico and the U.S., 2 countries differing in industrial status, served as participants. Eighty-eight Mexicans from Guadalajara and 88 Anglo Americans from Los Angeles, California read vignettes of a patient described to meet DSM-IV criteria for schizophrenia. In one vignette, the patient's disorder was characterized by predominantly positive symptoms (e.g., hallucinations, delusions), whereas in the other vignette negative symptoms (e.g., social withdrawal, apathy) predominated. In support of an attributional approach, negative symptoms were associated with greater perceived control than were positive symptoms. Correspondingly, negative symptoms were found to provoke more intense negative affect and less intense positive affect than were positive symptoms. Some national and gender differences were also found.  相似文献   
914.
915.
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   
916.
11beta-hydroxysteroid dehydrogenase type 1 (11beta-HSD-1) catalyses the interconversion of active cortisol and corticosterone with inert cortisone and 11-dehydrocorticosterone, thus regulating glucocorticoid access to intracellular receptors. In rats, chronic glucocorticoid excess or stress increases 11beta-HSD-1 in the hippocampus, producing suggestions that it may attenuate the deleterious effects of chronic glucocorticoid excess. However, 11beta-HSD-1 predominantly catalyses 11beta-reduction in the intact liver and hippocampal cells, thus regenerating active glucocorticoids from inert substrate. We studied 11beta-HSD activity in the tissues of male tree shrews following 28 days of sustained psychosocial stress or exogenous administration of cortisol. In the hippocampus, chronic psychosocial stress attenuated 11-HSD-1 activity (69 +/- 9% of control), whereas cortisol alone had no effect. In the liver, both chronic stress and cortisol administration decreased 11beta-HSD-1 activity (47 +/- 11% and 49 +/- 4% fall, resp.). Attenuation of 11beta-HSD-1 within tissues may reflect a homeostatic mechanism designed to minimise the adverse effects of prolonged stress and/or glucocorticoid excess.  相似文献   
917.
Clinical pragmatism: a method of moral problem solving   总被引:3,自引:0,他引:3  
This paper presents a method of moral problem solving in clinical practice that is inspired by the philosophy of John Dewey. This method, called "clinical pragmatism," integrates clinical and ethical decision making. Clinical pragmatism focuses on the interpersonal processes of assessment and consensus formation as well as the ethical analysis of relevant moral considerations. The steps in this method are delineated and then illustrated through a detailed case study. The implications of clinical pragmatism for the use of principles in moral problem solving are discussed.  相似文献   
918.
The background, rationale, methodology and outcomes of a project on developing local lifelong guidance strategies in four areas are outlined. The main components of the strategies developed in the four areas are analysed, and a number of issues relating to the process of strategy development are addressed. Much of the lack of coherence at local level stems from lack of coherence at national policy level: implications for national policy are examined. Finally, implications for parallel work in other localities are explored.  相似文献   
919.
We report the results of a prospective study of a random sample of 1353 elderly but healthy men and women who were followed up for a period of 10 yr, when mortality and cause of death were ascertained. Overall results have been reported elsewhere for mortality from cancer, coronary heart disease and other causes; here we are concerned with the personality factors predicting breast cancer, cervical cancer, cancer of the corpus uteri specifically, as well as other types of cancer in women. Ten specific hypotheses were tested, using specially constructed questionnaires for the purpose, and for most of these statistically significant support was obtained. The results justify belief that specific types of cancer may be related to specific stress/personality factors.  相似文献   
920.
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