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71.
We used two simple unsupervised machine learning techniques to identify differential trajectories of change in children who undergo intensive working memory (WM) training. We used self‐organizing maps (SOMs)—a type of simple artificial neural network—to represent multivariate cognitive training data, and then tested whether the way tasks are represented changed as a result of training. The patterns of change we observed in the SOM weight matrices implied that the processes drawn upon to perform WM tasks changed following training. This was then combined with K‐means clustering to identify distinct groups of children who respond to the training in different ways. Firstly, the K‐means clustering was applied to an independent large sample (N = 616, Mage = 9.16 years, range = 5.16–17.91 years) to identify subgroups. We then allocated children who had been through cognitive training (N = 179, Mage = 9.00 years, range = 7.08–11.50 years) to these same four subgroups, both before and after their training. In doing so, we were able to map their improvement trajectories. Scores on a separate measure of fluid intelligence were predictive of a child's improvement trajectory. This paper provides an alternative approach to analysing cognitive training data that go beyond considering changes in individual tasks. This proof‐of‐principle demonstrates a potentially powerful way of distinguishing task‐specific from domain‐general changes following training and of establishing different profiles of response to training.  相似文献   
72.
上世纪50年代,UFO目击者和加入这个事件的渲染者使事件急剧升温。1950年,弗朗克·斯库利(Frank Scully)发表了一本引起轰动的书,叫《追踪飞碟》。书中声称,一个飞碟坠毁在新墨西哥的阿兹特克东部的偏僻的高原沙漠上,飞碟的直径为99英尺,里面有16个外星人的尸体。斯库利自己并没有看见这个场景,仅仅是听别人说的。2年以后,发现这个故事是个骗局。关于飞碟坠毁的另一个故事也是发生在新墨西哥,地点是位于罗斯威尔西北部的75英里一处空军基地。据猜测,这次坠毁发生在1947年的7月,由此引发了一系列的事件和争论,并延续至今。坠毁是不容争论的,…  相似文献   
73.
Kidd SA  Kral MJ 《Adolescence》2002,37(146):411-430
This study presents the results of a qualitative analysis of the narratives of 29 street youth in which they describe their experiences with, and understanding of, suicide. A history of attempted suicide was reported by 76% of the participants and the analysis revealed themes of isolation, rejection/betrayal, lack of control, and most centrally, low self-worth as forming the basis of their experiences concerning suicide. Additionally it was found that trading sex, in which most participants had been or were currently involved, was linked with their suicidal experiences and may account for the high attempt rate. Finally, variables related to suicide were found that have not been examined previously in the literature on street youth, including loss of control, assault during prostituted sex, drug abuse as a "slow suicide," and breakups in intimate relationships.  相似文献   
74.
The authors examined emotion-specific patterns of appraisal, coping, and cardiovascular reactivity during real ongoing emotional episodes. In this study, 109 participants performed a neutral opinion-expression task, where a confederate elicited anger, shame, or pride using verbal and nonverbal behavior. The authors assessed cognitive appraisals, emotional reactions, coping, outcomes (state self-esteem and outcome satisfaction), and cardiovascular reactivity. Results indicated substantial and theoretically consistent differences between the 3 emotions (and differences from a nonemotion condition) for cognitive appraisals, self-reported coping, behavioral coping, self-esteem, and cardiovascular reactivity. The results are discussed in relation to their implications for emotion theory and for psychological and physical health. Overall, the results suggest that researchers can study emotion-related issues using authentic emotional reactions.  相似文献   
75.
In the first part of this paper we review evidence suggesting that there exists a mechanism that selects input on the basis of its similarity to the required action. This response-based input selection differs from the more established space- and object-based input selection in that it is not constrained by the structure of the input. Our evidence suggests that the two-choice Stroop effect is caused by this response-based selection mechanism. By contrast, it is known that the flanker effect is determined by the space- and object- based selection mechanisms. We explore whether the conflict resolution of the Stroop and flanker tasks is different as well by embedding these two tasks in a PRP (Psychological Refractory Period) paradigm. We show that the Stroop and the PRP effects are additive whereas the flanker and the PRP effects are underadditive, suggesting that the processes in charge of the conflict resolution in the Stroop and the flanker tasks are indeed different. We discuss possible reasons for this difference, and discuss possible ways in which the response-based mechanism can be implemented in information processing models.  相似文献   
76.
Numerous previous investigators have explained species differences in spatial memory performance in terms of differences in foraging ecology. In three experiments we attempted to extend these findings by examining the extent to which the spatial memory performance of echidnas (or "spiny anteaters") can be understood in terms of the spatio-temporal distribution of their prey (ants and termites). This is a species and a foraging situation that have not been examined in this way before. Echidnas were better able to learn to avoid a previously rewarding location (to "win-shift") than to learn to return to a previously rewarding location (to "win-stay"), at short retention intervals, but were unable to learn either of these strategies at retention intervals of 90 min. The short retention interval results support the ecological hypothesis, but the long retention interval results do not. Electronic Publication  相似文献   
77.
Confirmatory factor analysis and regression analyses of the Beavers Interactional Scales did not appear to support the model offered by its developers, namely, several specified family attributes contributing respectively to two global factors of Family Competence and Family Style. Moreover, regression analysis indicated that only three of 12 items predicted raters' assessments of Global Family Health, and one of seven items predicted Global Family Style. Individuals interested in the family dynamic centripetal/centrifugal might best think of that as a unitary entity and rate it accordingly.  相似文献   
78.
Alvin Plantingas Warranted Christian Belief is without questionone of the central texts of the Reformed epistemology movement. Critiques of Plantingas defence have been both multiple and varied. As varied as these responses are, however, it is my contention that many of them amount to the same thing. It is the purpose of this paper to offer an overview of the main lines of attack that have been directed as Plantingas project, and thereafter to show how many, if not most, of these objections can be understood as versions or aspects of the same criticism, what I call the Inadequacy Thesis.  相似文献   
79.
The authors of this essay suggest that the field of bioethics and Christian theology have a great deal to offer to each other. The authors first argue that representatives from both fields must first make sure that they fully and correctly represent their respective position. In other words, scientists, ethicists, and theologians alike must make sure that they present their fields and not use their knowledge merely for personal gain at the stake of misguiding people. Once this is established, the authors then proceed to show the intimate relationship between Christianity and medicine that has existed throughout the ages. It is a call for a continuation of such a relationship that the authors suggest between bioethics and theology. Through an integration of bioethics and Christian theology, both scientists/physicians and theologians are able to gain greater insight into the human person—a focus in both fields.  相似文献   
80.
Objectives: To understand the impact of physicians and patients religious/spiritual orientation on discussions of spiritual issues. Methods: We performed semi-structured interviews of 10 Missouri family physicians and 10 patients of these physicians, selecting subjects nonrandomly to represent a range of demographic factors, practice types, and chronic or terminal illness. We coded and evaluated transcribed interviews for themes. Results: Respondents expressed that similar belief systems facilitate patient–physician spiritual interactions and bring confidence to their relationships. Those holding dissimilar faiths noted limited ability to address spiritual questions directly. They cited significant barriers to spiritual interaction but considered that ecumenism, use of patient-centered care, and negotiation skills lessen these barriers. Conclusions: Our respondents view spirituality similarly to other aspects of the physician–patient relationship involving differing viewpoints. Where discordance exists, cross-cultural, patient-centered, diplomatic approaches facilitate spiritual discussions.  相似文献   
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