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121.
The present study investigated the use of perceptual binding processes in schizophrenic (SC) patients and matched healthy controls, by examining their performance on the recall of symmetrical (vertical, horizontal and diagonal) and asymmetrical patterns varying in length between 2 and 9 items. The results showed that, although SC patients were less accurate than controls in all conditions, both groups recalled symmetrical patterns better than asymmetrical ones. The impairment of SC patients was magnified with supra-span symmetrical arrays, and they were more likely to reproduce symmetrical patterns as asymmetrical, particularly at medium and high length levels. Hierarchical regression analyses further indicated that the between-group differences in the recall of supra-span vertical and horizontal arrays, which require a greater involvement of visual pattern processes, remained significant after removing the variance associated with performance on asymmetrical patterns, which primarily reflects intrafigural spatial processes. It is proposed that schizophrenia may be associated with a specific deficit in the formation and retrieval of the global visual images of studied patterns and in the use of the on-line information about the type of symmetry being tested to guide retrieval processes.  相似文献   
122.
Precursors of the reliability generalization (RG) meta‐analytic approach have not established a single preferred analytic method. By means of five real RG examples, we examine how using different statistical methods to integrate coefficients alpha can influence results in RG studies. Specifically, we compare thirteen different statistical models for averaging reliability coefficients and searching for moderator variables that differ in terms of: (a) whether to transform or not the coefficients alpha, and (b) the statistical model assumed, distinguishing between ordinary least squares methods, the fixed‐effect (FE) model, the varying coefficient (VC) model, and several versions of the random‐effects (RE) model. The results obtained with the different methods exhibited important discrepancies, especially regarding moderator analyses. The main criterion for the model choice should be the extent to which the meta‐analyst intends to generalize the results. RE models are the most appropriate when the meta‐analyst aims to generalize to a hypothetical population of past or future studies, while FE and VC models are the most appropriate when the interest focuses on generalizing the results to a population of studies identical to those included in the meta‐analysis. Finally, some guidelines are proposed for selecting the statistical model when conducting an RG study.  相似文献   
123.
The objective of this paper is to make a rhetorical analysis of the op-ed entitled ‘Finding design in nature’ by Cardinal Christoph Schönborn, Archbishop of Vienna, published by The New York Times in 2005, three months after the death of John Paul II. In this essay, the Cardinal states that it is an error to affirm that Catholic doctrine is compatible with the ‘neo-Darwinist’ theory of evolution and that the Roman Catholic Church accepts that theory. For the Archbishop, the origin of this error lies in the abuses committed in the interpretation of John Paul's 1996 speech in which the Pope declared that evolution was more than a hypothesis and took a more favourable stance towards evolutionary theory than his predecessors. In his article, the Cardinal describes that papal message as ‘vague and unimportant’. We interpret Cardinal Schönborn's position as a personal rhetorical change with respect to John Paul II's 1996 speech. In our view, the Archbishop directs his criticism against evolutionary theory not only because of its scientific theories (not rejected by Church Magisterium) but also for being potentially dangerous in its use by certain authors as a scientific argument in support of their atheism.  相似文献   
124.
This essay will address the ethical issues that have emerged in the first considerations of the newly emerging stem cell technology. Many of us in the field of bioethics were deliberating related issues as we first learned of the new science and confronted the ethical issues it raised. In this essay, I will draw on the work of colleagues who were asked to reflect on early stages of the research (members of the IRBs, the Geron Ethicist Advisory Board, and the National Bioethics Advisory Commission) as the field debated the issues of consent, moral status, use of animal tissues, abortion, use of fetal tissue, and the nature and goals of entrepreneurial research. In this new capacity, ethicists weighed the problem of privacy, the role of justice considerations, and the issues of the marketplace in science. At this point, it is clear that far more issues remain unresolved than are settled, that there is largely unexplored territory ahead, and that the single most important task that faces us as a field is a steady call for ongoing conversation and public debate.  相似文献   
125.
Individuals with autism spectrum disorder (ASD) show atypical patterns of learning and generalization. We explored the possible impacts of autism-related neural abnormalities on perceptual category learning using a neural network model of visual cortical processing. When applied to experiments in which children or adults were trained to classify complex two-dimensional images, the model can account for atypical patterns of perceptual generalization. This is only possible, however, when individual differences in learning are taken into account. In particular, analyses performed with a self-organizing map suggested that individuals with high-functioning ASD show two distinct generalization patterns: one that is comparable to typical patterns, and a second in which there is almost no generalization. The model leads to novel predictions about how individuals will generalize when trained with simplified input sets and can explain why some researchers have failed to detect learning or generalization deficits in prior studies of category learning by individuals with autism. On the basis of these simulations, we propose that deficits in basic neural plasticity mechanisms may be sufficient to account for the atypical patterns of perceptual category learning and generalization associated with autism, but they do not account for why only a subset of individuals with autism would show such deficits. If variations in performance across subgroups reflect heterogeneous neural abnormalities, then future behavioral and neuroimaging studies of individuals with ASD will need to account for such disparities.  相似文献   
126.
Although dependence in effect sizes is ubiquitous, commonly used meta-analytic methods assume independent effect sizes. We describe and illustrate three-level extensions of a mixed effects meta-analytic model that accounts for various sources of dependence within and across studies, because multilevel extensions of meta-analytic models still are not well known. We also present a three-level model for the common case where, within studies, multiple effect sizes are calculated using the same sample. Whereas this approach is relatively simple and does not require imputing values for the unknown sampling covariances, it has hardly been used, and its performance has not been empirically investigated. Therefore, we set up a simulation study, showing that also in this situation, a three-level approach yields valid results: Estimates of the treatment effects and the corresponding standard errors are unbiased.  相似文献   
127.
Categories, as mental structures, are more than simply sums of property frequencies. A number of recent studies have supported the view that the properties of categories may be organised along functional lines and possibly dependency structures more generally. The study presented here investigates whether earlier findings reflect something unique in the English language/North American culture or whether the functional structuring of categories is a more universal phenomenon. A population of English-speaking Americans was compared to a population of Cantonese-speaking Hong Kong Chinese. The findings clearly support the view that functional influences on category centrality are universal (or at least common to Cantonese-speaking Hong Kong Chinese and English-speaking Americans), albeit with specific cross-cultural/cross-linguistic group differences in the particular properties that are considered central to categories.  相似文献   
128.
Abstract

Work meaning patterns combine dimensions such as work centrality, expressive versus economic work goals, and entitlement versus obligation societal norms into a holistic picture of the evolution over time of the meaning of work. Data from a longitudinal study in eight countries are used to establish major work meaning patterns and to study their stability during early career paths. Further, some potential determinants of these work meaning patterns are analysed and their consequences for later careers are considered. Statistical analyses include: cluster analysis, multiple discriminant analysis, analysis of covariance combined with multiple classification analysis, analysis of variance, and chi-square analysis. Five cross-national work meaning patterns are identified for machine operators in their third year in the labour market. One-third of the sample had remained in the same work meaning pattern for 2 years, while two-thirds had changed their work pattern. Respondents' age, country, prior work environment, and prior work socialization behaviours and outcomes have an impact on work meanings held 2 years later. In addition the respondent's work meaning pattern allows subsequent career enhancing strategies and effort expenditure at the job to be predicted.  相似文献   
129.
There have been a small number of investigations of alexithymia in multiple sclerosis (MS) using the 20-item Toronto Alexithymia Scale (TAS-20). However, the TAS-20 factor structure has not yet been evaluated in a MS patient sample, and earlier Spanish translations of this instrument require some improvement. We aimed to evaluate the factorial validity and reliability of an improved Spanish translation of the TAS-20 (the TAS-20-S). The TAS-20-S was completed by 221 MS patients. Confirmatory factor analysis was used to compare the fit of six different factor models. Internal consistency and retest reliability coefficients were also computed. The correlated three-factor model and the higher-order factor model made up of Difficulty Identifying Feelings, Difficulty Describing Feelings, and Externally Oriented Thinking achieved the best fit. Alpha coefficients ranged between .87 and .67; mean inter-item correlations ranged between .48 and .20; and retest correlations after 6 months ranged between .61 and .52. A high degree of alexithymia was present in 18.1% of the sample. Reliability and the traditional three-factor structure were demonstrated for the TAS-20-S, which can now be recommended for assessing an aspect of emotional processing in MS patients.  相似文献   
130.
The research focused on the development of scientific production measurements implies a detailed and quite accurately procedure to avoid errors and misinterpretations by third parties. The use of public researcher profiles such as the Researcher ID among others, may appeal to simplify the process of direct search on databases. The purpose of this research is to analyze the Researcher ID profile as an indicator of scientific productivity in a sample of 8 Spanish professors of Personality, Evaluation and Psychological Treatment area and compare these professors searching them in the Web of Science, also respond to a disagreement generated from a previous study published in Psicothema and culminated in a letter, as that there are unfounded arguments exposed. The results show that there are inaccuracies in the Researcher ID's and therefore cannot be used as an indicator of scientific production, since this tool allows to include any record type (letters, meeting abstracts, etc…) even unrelated content to the Web of Science. These findings are discussed a view to the disagreement and previously mentioned and generated in Psicothema.  相似文献   
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