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101.
Primates can learn to categorize complex shapes, but as yet it is unclear how this categorization learning affects the representation of shape in visual cortex. Previous studies that have examined the effect of categorization learning on shape representation in the macaque inferior temporal (IT) cortex have produced diverse and conflicting results that are difficult to interpret owing to inadequacies in design. The present study overcomes these issues by recording IT responses before and after categorization learning. We used parameterized shapes that varied along two shape dimensions. Monkeys were extensively trained to categorize the shapes along one of the two dimensions. Unlike previous studies, our paradigm counterbalanced the relevant categorization dimension across animals. We found that categorization learning increased selectivity specifically for the category-relevant stimulus dimension (i.e., an expanded representation of the trained dimension), and that the ratio of within-category response similarities to between-category response similarities increased for the relevant dimension (i.e., category tuning). These small effects were only evident when the learned category-related effects were disentangled from the prelearned stimulus selectivity. These results suggest that shape-categorization learning can induce minor category-related changes in the shape tuning of IT neurons in adults, suggesting that learned, category-related changes in neuronal response mainly occur downstream from IT.  相似文献   
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103.
Using Ecological Momentary Assessment, the within patient associations between drive for thinness, emotional states, momentary urge to be physically active and physical activity were studied in 32 inpatients with an eating disorder. Participants received an electronic device and had to indicate at nine random times a day during 1 week their momentary drive for thinness, positive and negative emotional states and their urge to be physically active and physical activity. Multilevel analyses indicated that patients with higher mean levels for urge to be physically active were characterized by lower body mass index (BMI) and chronically negative affect whereas patients with higher mean levels for physical activity were characterized by lower BMI and higher dispositions for drive for thinness. In addition, within patient relations between drive for thinness and urge to be physically active were moderated by BMI and chronically negative affect whereas within patient relations between drive for thinness and physical activity were moderated by BMI. Finally, also positive emotional states were significantly associated with physical activity within patients. By using a daily process design, characteristics of physical activity were revealed that have not been identified with assessment methods that have a lower time resolution.  相似文献   
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105.
This study investigates associations between depressive problems and classroom social status in a large population cohort of Dutch early adolescents (N = 1046, age 13.52 +/- 0.51, 52.4% girls). Depressive problems were assessed by parent and self-reports and classroom status by peer nominations. We assessed peer status with respect to both achievement-related (being a good learner, being good at sports, being good-looking) and affection-related (being liked, being disliked, being best friend) areas. In boys, depressive problems were most strongly associated with not being good at sports, while in girls the association was strongest for not being liked. The risk of a low status in one area could largely be compensated by a high status in another area.  相似文献   
106.
The advice to musicians and marketers is to focus on what they love: a truism for practitioners is to find 1000 ‘true fans’ and make $100 from each of them (Kelly, 2008. 1000 True fans. The Technium). If this advice is correct, we should see musicians with loyal user bases engaging more with their favourite artists and less with other music, suggesting a narrow targeting strategy would suffice. On the other hand, the established marketing laws indicate that the listeners of very different genres should overlap more than conventional wisdom would suggest, supporting the need for a much broader approach to targeting potential audiences. Given these conflicting views, musicians need to know if they should market to their existing listeners, the listeners of music similar to theirs (i.e., the same genre), or if they should try to reach a much wider audience. We turn to established choice patterns from the marketing literature to address these questions in the music context. This study examines 84,000,000 observations of music listening from 27,000 unique global users between 2013 and 2014 and survey data from 2019 containing music listening from over 1000 representative respondents in the United States. The results show that listening follows the Duplication of Purchase law for genres, artists, albums, and songs, at an annual, 6-months, 3-months, 1-month, and 1-week period, with no indication of partitioned music listening. The implication is that musicians should try to reach all potential listeners, regardless of what they already listen to. These findings contribute to the theoretical knowledge about duplication analyses of various durations, extend the contexts of choice behaviour that exhibit this pattern, and managerially, to knowledge about the extent of potential audiences and ‘share of ear’ competition.  相似文献   
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108.
The aim of this article is to review and evaluate behavioral and physiological measurement techniques frequently used to assess dental anxiety and fear in children. Attention is given to the data collected, the empirical findings obtained, and the availability of normative data. The main focus, however, is on the reliability and validity. Results show that all questionnaires are open to criticism. Of the behavioral measures, Melamed's Behavior Profile Rating Scale is to be preferred to Frankl's Rating Scale, Venham Rating Scales, and Visual Analogue Scales. The main reasons are that Melamed's BPRS measures the behavior of the child more precisely and that it has superior psychometric properties. Furthermore, because of their practical, conceptual, and psychometric problems, physiological measures at this stage are found to be less appropriate for assessing dental fear in children. It is concluded that a behavioral measure is not always the ideal, but often the only available technique for assessing dental fear in children.  相似文献   
109.
The style of a set of Swedish nursery tunes is described in terms of a generative rule system. A generative rule system producing melodically similar versions of an old Swedish folk song is also presented. Examples of melodies generated by these two rule systems are given.Both these rule systems are similar in several respects. Thus, the marking of the hierarchical constituent structure seems to be one of the important principles in composing simple melodies.The rule systems also show a number of similarities with the Chomsky & Halle (1968) generative phonology of English. For instance, the procedures used for deriving a stress contour from a tree diagram are almost identical. Moreover, in sentences as in melodies this stress, or prominence contour is of decisive importance to the generation of the surface structure, such as meter, harmony, and sequences of pitches. It is believed that such parallels between language and music reflect characteristics of man's perceptual and cognitive capacities.  相似文献   
110.
Johan van Benthem 《Synthese》1982,51(3):431-472
The relation between logic and philosophy of science, often taken for granted, is in fact problematic. Although current fashionable criticisms of the usefulness of logic are usually mistaken, there are indeed difficulties which should be taken seriously — having to do, amongst other things, with different scientific mentalities in the two disciplines (section 1). Nevertheless, logic is, or should be, a vital part of the theory of science. To make this clear, the bulk of this paper is devoted to the key notion of a scientific theory in a logical perspective. First, various formal explications of this notion are reviewed (section 2), then their further logical theory is discussed (section 3). In the absence of grand inspiring programs like those of Klein in mathematics or Hilbert in metamathematics, this preparatory ground-work is the best one can do here. The paper ends on a philosophical note, discussing applicability and merits of the formal approach to the study of science (section 4).I would like to thank David Pearce and Veikko Rantala for their helpful comments.  相似文献   
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