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161.
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   
162.
Background and objectives: Terrorism can heighten fears and undermine the feeling of safety. Little is known, however, about the factors that influence threat and safety perception after terrorism. The aim of the present study was to explore how proximity to terror and posttraumatic stress reactions are associated with perceived threat and safety after a workplace terrorist attack. Design and methods: A cross-sectional questionnaire survey was administered to employees in 14 of 17 Norwegian ministries 9–10 months after the 2011 bombing of the government headquarters in Oslo (n = 3520). Results: About 198 of 1881 employees completing the survey were at work when the bomb exploded. Regression analysis showed that this high-exposed group had elevated perceived threat (β = 0.36; 95% CI = 0.19 to 0.53) and reduced perceived safety (β = ?0.42; 95% CI = ?0.62 to ?0.23) compared to a reference group of employees not at work. After adjusting for posttraumatic stress reactions, however, proximity to the explosion no longer mattered, whereas posttraumatic stress was associated with both high perceived threat (β = 0.55; 95% CI = 0.48 to 0.63) and low perceived safety (β = ?0.71; 95% CI, ?0.80 to ?0.63). Conclusion: Terror-exposed employees feel more threatened and less safe after a workplace terrorist attack, and this is closely linked to elevated levels of posttraumatic stress reactions.  相似文献   
163.
This study tested the hypothesis that family members showing greater commonality (similarity) and sociality (predictive accuracy) in their construing of family relationships would display greater satisfaction with those relationships than would individuals in families whose relational construing was more discrepant and unpredictable. Forty-seven family triads participated in the study, including a mother, father, and adolescent from each family. Measures of commonality and sociality in the construction of family relationships derived from a family relationships grid were compared to measures of family structure, including the Family Cohesion and Adaptability Evaluation Scale (FACES-II) (Olson, Portner, & Bell, 1982) and the Parent-Adolescent Communication Scale (PACS) (Barnes & Olson, 1982). The findings suggest that members' perceptions of the family as emotionally close, flexible, and communicative may not represent independent aspects of the family structure, at least within the present nonclinical sample. Comparison of the family relationship grids with the FACES-H and PACS demonstrated that commonality and sociality among family members was highly related to mothers' and adolescents' family satisfaction, but was much less predictive of that of the father.  相似文献   
164.
Initial evidence indicates that face-based judgements of socially relevant characteristics such as people's trustworthiness or attractiveness are linked to the configural/holistic processing of facial cues. What remains a matter of debate, however, is whether such processing is actually necessary for normal social judgements to occur and whether it resembles the type of integrative processing as required for facial identification. To address these issues, we asked a well-characterized case of acquired prosopagnosia (PS) with a marked deficit in holistic processing for face identity to rate a series of faces on several dimensions of social relevance. PS provided ratings within the normal range for most of the social characteristics probed (i.e., aggression, attractiveness, confidence, intelligence, sociability, trustworthiness). Her evaluations deviated from those of healthy controls only when facial dominance was concerned. Taken together, these data demonstrate that the inability to integrate facial information during face individuation does not necessarily translate into a generalized deficit to evaluate faces on social dimensions.  相似文献   
165.
The emergence of synthetic biology holds the potential of a major breakthrough in the life sciences by transforming biology into a predictive science. The dual-use characteristics of similar breakthroughs during the twentieth century have led to the application of benignly intended research in e.g. virology, bacteriology and aerobiology in offensive biological weapons programmes. Against this background the article raises the question whether the precautionary governance of synthetic biology can aid in preventing this techno-science witnessing the same fate? In order to address this question, this paper proceeds in four steps: it firstly introduces the emerging techno-science of synthetic biology and presents some of its potential beneficial applications. It secondly analyses contributions to the bioethical discourse on synthetic biology as well as precautionary reasoning and its application to life science research in general and synthetic biology more specifically. The paper then identifies manifestations of a moderate precautionary principle in the emerging synthetic biology dual-use governance discourse. Using a dual-use governance matrix as heuristic device to analyse some of the proposed measures, it concludes that the identified measures can best be described as “patchwork precaution” and that a more systematic approach to construct a web of dual-use precaution for synthetic biology is needed in order to guard more effectively against the field’s future misuse for harmful applications.  相似文献   
166.
This article reports on a study of children's deductive reasoning in solving novel relational problems. Detailed protocols were obtained from 264 children (aged 9- 12 years) who verbalised their thinking as they solved the problems. The study included the development of a three-phase theory based on Johnson-Laird and Byrne's mental models perspective, but with some distinct modifications. These include a focus on the relational complexity entailed in model construction and in premise integration, and the advancement of four reasoning principles that are applied throughout problem solution (in contrast to Johnson-Laird's falsification processes as the hallmark of deductive reasoning). The reported case studies and the results of statistical analyses supported predictions arising from the proposed theory, including the key role of the reasoning principles. The results also showed that problem difficulty is a function of relational complexity, not of the number of models to be constructed, as argued by Johnson-Laird and Byrne.  相似文献   
167.
In this diary study, we tested the recovery potential of exercise activities during leisure time and examined the psychological mechanisms underlying the relation between exercise activities and affect. We hypothesized that spending time on exercise activities after work will be related to subsequent affect in the evening, and that psychological detachment from work, sense of belonging, and physical self-perceptions explain why exercise activities are related to subsequent affect. One-hundred and twenty-six participants from diverse occupations completed a diary twice a day over five consecutive work days. Multilevel analyses showed that exercise activities after work were related to positive, but not to negative affect in the evening. As proposed, psychological detachment, sense of belonging, and physical self-perceptions mediated the relation between exercise activities after work and positive affect in the evening.  相似文献   
168.
A questionnaire was completed by 98 Muslim and 91 non-Muslim Australian women to examine the relationship between Islam and body image. Path analyses revealed that for Muslim women (but not non-Muslim women) strength of religious faith was inversely related to body dissatisfaction, body self-objectification, and dietary restraint. These relationships were mediated by increased use of modest clothing and by reduced media consumption. These results are consistent with the proposition that adherence to Islam can indirectly protect women's body image from appearance-based public scrutiny and from exposure to Western media.  相似文献   
169.
Previous studies using the Animals Fluency Test have shown that dementia patients with Alzheimer's disease (AD), Huntington's disease (HD), or Parkinson's disease (PD) produce fewer correct words and have smaller semantic cluster sizes than controls or PD patients without dementia (PDND). Although the number of correct words generated by the patients with AD was positively correlated with mental status, cluster size, surprisingly, was not. To increase word output and increase the reliability of estimates of cluster size, semantic fluency was reexamined using the Supermarket Fluency Task. Overall, patients with HD or PD with dementia (PDD) exhibited reduced cluster sizes compared to older controls or PDND patients, but cluster sizes were only marginally reduced for patients with AD. These effects were evident only for female participants, because the cluster sizes for elderly control men were substantially smaller than those of elderly women. For the female patients with AD, cluster size was correlated with mental status, but the relationship was nonlinear. Cluster size was normal for mildly demented patients with AD, but much reduced for moderately or severely demented participants. In contrast to a previous report, in the present study the proportion of category labels generated was increased for patients with HD with dementia but not for patients with AD. This finding questions one line of evidence that semantic memory stores undergo “bottom-up” degradation in AD. Together with previous results, these findings indicate that semantic cluster size reflects efficiency of access to semantic knowledge which is similarly compromised in subcortical and cortical diseases.  相似文献   
170.
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