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871.
In this paper, we examine whether color and shape, tied to a single object in space, (1) are identified and selected in series or in parallel, (2) are identified and selected in a dependent, self-terminating manner or in an independent and exhaustive manner, and (3) are conjoined by a feature integration process before or only after an initial stage of separate attribute analyses has finished. We measured response time and the selection negativity (SN) derived from event-related brain potentials when participants responded to a unique conjunction of color and shape in a go/no-go target detection task. The discriminability of the color and the shape of the conjunction was manipulated in three conditions. When color and shape were easy to discriminate, the SNs to color and shape started at the same time. When one attribute was less discriminable, the SN to that attribute started later, but not the SN to the complementary attribute. This suggests that color and shape are identified and selected in parallel. In all three discriminability conditions, the SNs to color and shape were initially independent but later interacted. This suggests that color and shape are initially selected independently and exhaustively, after which their conjunction is analyzed. The SN to local shape features started later than that to the conjunction of color and global shape features, which suggests that feature integration can start before the analyses of the separate attributes have finished. 相似文献
872.
Lorraine G. Allan Shepard Siegel Chandani Kulatunga-Moruzi Thomas Eissenberg C. Andrew Chapman 《Attention, perception & psychophysics》1997,59(8):1327-1334
In the typical induction of the orientation-contingent color aftereffect (CCAE), the stimuli are composed of elements that differ in both color and luminance. Three experiments are reported that show that chromatic contrast between stimulus elements is insufficient for the induction of the orientation-CCAE and that luminance contrast is necessary. These experiments expand on previous research concerned with the role of luminance contrast in the induction of orientation-CCAEs by eliminating alternative explanations. 相似文献
873.
Mark A. Barnett Guy D. Vitaglione Kimberly K. G. Harper Steven W. Quackenbush Lee Ann Steadman Birgit S. Valdez 《Journal of applied social psychology》1997,27(15):1316-1334
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
874.
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
875.
Curtis W. Hart Robin Scroggs Claude Barbre Antoinette Goodwin Philip Paris Mark J. Hanson Kathryn Madden Annette G.E. Esser Raymond J. Lawrence Jr. Jilisa Snyder Karen A. Monk George M. Klee Loy McGill Jill Carlen Kirby Thandeka Pamela Davis Barnett Gregory Forte J.J. Haines Barry Ulanov Elizabeth MacDonald 《Journal of religion and health》1997,36(1):81-104
876.
877.
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
878.
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
879.
A. G. Watts Ruth Hawthorn Jill Hoffbrand Heather Jackson Andrea Spurling 《British Journal of Guidance & Counselling》1997,25(2):217-227
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
880.
Paul M. Kohn Colleen O'Brien Donna I. Pickering 《Personality and individual differences》1997,22(6):895-899
Adaptiveness constitutes coping consistently with Stressors so to reduce distress or, at worst, not aggravate it. Accordingly, it should moderate the adverse impact of hassles. Undergraduate volunteers (N = 200) responded to measures of hassles, adaptiveness, and the criteria of subjective distress, psychiatric symptomatology and minor physical ailments. In all three regression analyses, hassles made a substantial positive contribution and adaptiveness a small negative contribution to adverse outcome. The interaction between hassles and adaptiveness was non-significant in all three cases. Alternative interpretations were identified to guide further research. 相似文献