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141.
CLUSTERS PRECEDE SHAPES IN PERCEPTUAL ORGANIZATION 总被引:2,自引:0,他引:2
Abstract —Does perceptual grouping require attention? Recent controversy on this question may be caused by a conflation of two aspects of grouping: element clustering (determining which elements belong together) and shape formation (determining cluster boundaries). In Experiment 1, observers enumerated diamonds that were drawn with either lines or dots. These two types of stimuli were subitized (enumerated rapidly and accurately in the range from one to three items) equally well, suggesting that clustering dots into countable entities did not detnand attention. In contrast, when target diamonds were enumerated among distractor squares in Experiment 2. only line-drawn items could be subitized. We propose that clustering and shape formation not only involve different perceptual processes, but play different functional roles in vision. 相似文献
142.
Bresnahan JF 《America》1997,176(3):8-10, 12-16
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The authors examined the role of "perceived loomingness" in fear of HIV. Perceived loomingness refers to perceptions of rapid forward movement and instantaneous changes in the distance and danger of a potential threat (Riskind, 1992). One hundred and twenty undergraduates rated vignettes of two public encounters with an HIV-positive stranger. High-HIV fear subjects perceived greater loomingness and danger in these vignettes than did low-HIV fear subjects. Regression analyses that tested for a mediated model confirmed that the perceptions of loomingness may spark threat cognitions (such as the probability and imminence of harm), which, in turn, lead to fear. As predicted by the harm-looming model, loomingness also had some effects on fear that were not mediated by such standard threat cognitions. 相似文献
145.
James M. Gustafson 《Zygon》1995,30(2):177-190
Abstract. Theology and ethics intersect with sciences at different points depending upon whether the scholars involved are interested in, for example, general epistemological issues or practical moral judgments. The intersection affects theology and ethics in different ways, depending upon various commitments or resistances on the part of theologians. The author surveys his own writings to show how openness to the sciences has had an impact on various phases of his work and what issues remain somewhat unresolved. 相似文献
146.
James Gilbert 《Zygon》1995,30(4):531-539
Abstract. The development of Ralph Wendell Burhoe's philosophy of religion and science occurred in the shadow of the continuing dialogue about the place of science in American society. Like his friend and mentor, Harvard astronomer Harlow Shapley, Burhoe was distressed and intrigued by the troubled postwar relations between science and religion. Unlike Shapley, however, Burhoe sought to create a new modernism, a blend of religion and science that would allow each to develop and complement the other. 相似文献
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148.
Clinicians are commonly asked to participate in the determination of an individual's mental capacity and susceptibility to undue influence. Vague statutory definitions and lack of operational criteria for both determinations have contributed to inconsistency in the quality and usefulness of expert input to these determinations. Questionnaire responses of 119 probate judges from the U.S. indicate that this input is quite influential despite the problems mentioned above. This paper presents and discusses the judges' views on selected procedural and conceptual aspects of expert evaluation and testimony. 相似文献
149.
Recent evidence suggests a larger role for personality determinants of the coping response than has been traditionally held. In the two studies presented here, we examined the influence of personality on the use of social support and other coping strategies in samples of undergraduate students. The first study surveyed a range of coping responses to naturally occurring stressors and found that Extraversion was related to social support seeking, optimism (identified as germane to coping in prior research) was related to problem solving, and both dispositions were negatively related to avoidance. The second study used an experimental approach and multiple personality measures to correct for possible methodological problems in the first. Extraversion again proved to be associated with help seeking; moreover, this relationship accounted for that of another disposition, self-esteem—a construct considered crucial in the literature. The utility of personality variables, particularly Extraversion, in predicting and explaining the choice of a coping strategy is discussed. 相似文献
150.
Despite the importance of the issue for AIDS-related research, there is a paucity of studies that have addressed the issue of the validity of self-reports of patterns of risk behavior over time. This article frames issues of measurement in the context of cognitive psychology and presents a research paradigm that investigators can use to explore issues of accuracy, bias, and stability in self-reports. The paradigm also permits the analysis of transitory influences on risk behavior, influences which have been minimized in current AIDS research. Preliminary data are presented that support the feasibility of the method and which are suggestive of important considerations in the development of valid measures in national surveys. 相似文献