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871.
We analyze four general signal detection models for recognition memory that differ in their distributional assumptions. Our
analyses show that a basic assumption of signal detection theory, the likelihood ratio decision axis, implies three regularities
in recognition memory: (1) the mirror effect, (2) the variance effect, and (3) the z-ROC length effect. For each model, we
present the equations that produce the three regularities and show, in computed examples, how they do so. We then show that
the regularities appear in data from a range of recognition studies. The analyses and data in our study support the following
generalization: Individuals make efficient recognition decisions on the basis of likelihood ratios. 相似文献
872.
Imagining the Future of Photoacoustic Mammography 总被引:1,自引:0,他引:1
van der Burg S 《Science and engineering ethics》2009,15(1):97-110
How can a realistic ethical imagination about the future of a technology take shape? This article contains a reflection which is based on the experiences of an embedded ethicist in the context of biophysical research conducive to the development of photoacoustic mammography, which is intended for the non-invasive detection of breast cancer. Imagination in this context already informs the activities of the biophysical researchers, but its role is limited: biophysical future scenarios concentrate on the technological advances that photoacoustics could bring about. In this article it is argued that it is advisable to also consider the medical practice and the ways in which this practice is likely to change as an effect of the introduction of photoacoustic mammography into it. On the basis of this more encompassing imaginative endeavor it is possible to get a clearer idea about how new technologies are able to contribute to human well being, which is informative for the setting of research-goals/priorities and a responsible implementation of new technologies into the world. 相似文献
873.
Rosa A. Hoekstra Meike Bartels Marieke van Leeuwen Dorret I. Boomsma 《Developmental science》2009,12(6):1041-1053
The etiology of individual differences in general verbal ability, verbal learning and letter and category fluency were examined in two independent samples of 9‐ and 18‐year‐old twin pairs and their siblings. In both age groups, we observed strong familial resemblance for general verbal ability and moderate familial resemblance for verbal learning, letter and category fluency. All familial resemblance was explained by genetic factors. There was significant covariance among the tests, which was stronger in magnitude in the adolescent cohort. The covariance was mainly explained by genetic effects shared by subtests, both in middle childhood and in late adolescence. In addition to a shared set of genes that influenced all phenotypes, there were also genetic influences specific to the different verbal phenotypes. 相似文献
874.
875.
McCullough LB McGuire AL Whitney SN 《The American journal of bioethics : AJOB》2007,7(12):49-50; discussion W3-4
876.
The present research examined the relationship between adherence to honor norms and emotional reactions after an insult. Participants were 42 Dutch male train travelers, half of whom were insulted by a confederate who bumped into the participant and made a degrading remark. Compared with insulted participants with a weak adherence to honor norms, insulted participants with a strong adherence to honor norms were (a) more angry, (b) less joyful, (c) less fearful, and (d) less resigned. Moreover, insulted participants with a strong adherence to honor norms perceived more anger in subsequent stimuli than not-insulted participants with a strong adherence to these norms. The present findings support a direct relationship among insult, adherence to honor norms, and emotional reactions. 相似文献
877.
Harris LT McClure SM van den Bos W Cohen JD Fiske ST 《Cognitive, affective & behavioral neuroscience》2007,7(4):309-316
The medial prefrontal cortex (MPFC) reliably activates in social cognition and reward tasks. This study locates distinct areas
for each. Participants made evaluative (positive/negative) or social (person/not a person) judgments of pictured positive
or negative people and objects in a slow event-related design. Activity in an anterior rostral region (arMPFC) was significantly
greater for positive than for negative persons but did not show a valence effect for objects, and this was true regardless
of the judgment task. This suggests that the arMPFC is tuned to social valence. Interestingly, however, no regions of the
MPFC were found to be responsive to social information independently of valence. A region-of-interest analysis of the paraanterior
cingulate cortex (pACC), previously implicated in reward processing, demonstrated sensitivity to the valence of all stimuli,
whether persons or objects, across tasks. Affective evaluation may be a general function of the MPFC, with some regions being
tuned to more specific domains of information (e.g., social) than are others. 相似文献
878.
This study examined the role of media body comparison as a mediator of the relationships between psychological factors and sociocultural pressures to be thin and body dissatisfaction in both females and males. Participants were 1,386 females (mean age = 19.37 years) and 1,130 males (mean age = 19.46) from diverse backgrounds who completed a self-report questionnaire. Path analysis was used to test a cross-sectional model in which media body comparison mediated the impact of self-esteem, depressive mood, parent dieting environment, friend dieting, TV exposure, magazine message exposure, weight teasing and body mass index (BMI) on body dissatisfaction. In females, media body comparison partially or fully mediated relationships between self-esteem, depressive mood, friend dieting, magazine message exposure and BMI, and body dissatisfaction. In males, media body comparison was not a significant predictor of body dissatisfaction. This research particularly highlights the need to further examine processes that are involved in the development of body dissatisfaction in males. 相似文献
879.
880.
Esther van Leeuwen 《European journal of social psychology》2007,37(4):661-671
In this paper, the December 2004 tsunami tragedy was used as a background to investigate beliefs about intergroup helping. The general aim of the research was to test the proposal that helping can be used to reaffirm a threatened social identity. Two experiments conducted with Dutch participants (N = 78 and N = 73) tested the hypothesis that a threatened Dutch national identity would result in stronger preferences for help to the victims of the tsunami, but only in a domain that is positively and distinctly related to that national identity (i.e. water management). Results from both studies confirmed this hypothesis. Study 2 also showed a reversal of this effect in a domain negatively related to that identity. Moreover, perceived identity threat in Study 2 reduced over time in the high threat condition but not in the low threat condition, and this reduction was positively associated with the endorsement of water management help. Also, as predicted, in both studies a threatened national identity resulted in stronger beliefs that Dutch relief organisations should stay in control over their aid. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献