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631.
The purpose of this study was to investigate the relationships between selected tests of spatial orientation ability. 2 tests which have been used as predictors of spatial ability (Guilford-Zimmerman Aptitude Survey, Parts V and VI) plus 2 newly developed tests designed to measure that ability were given to 202 Junior high school boys aged 11-15 yr. 3 of these tests were of the paper and pencil type while one was a physical performance (tumbling) test. The paper-and-pencil tests correlated significantly with each other (.62, .61, .44) but the physical performance test did not correlate significantly with any of the other tests.  相似文献   
632.
Group-level variance estimates of zero often arise when fitting multilevel or hierarchical linear models, especially when the number of groups is small. For situations where zero variances are implausible a priori, we propose a maximum penalized likelihood approach to avoid such boundary estimates. This approach is equivalent to estimating variance parameters by their posterior mode, given a weakly informative prior distribution. By choosing the penalty from the log-gamma family with shape parameter greater than 1, we ensure that the estimated variance will be positive. We suggest a default log-gamma(2,λ) penalty with λ→0, which ensures that the maximum penalized likelihood estimate is approximately one standard error from zero when the maximum likelihood estimate is zero, thus remaining consistent with the data while being nondegenerate. We also show that the maximum penalized likelihood estimator with this default penalty is a good approximation to the posterior median obtained under a noninformative prior. Our default method provides better estimates of model parameters and standard errors than the maximum likelihood or the restricted maximum likelihood estimators. The log-gamma family can also be used to convey substantive prior information. In either case—pure penalization or prior information—our recommended procedure gives nondegenerate estimates and in the limit coincides with maximum likelihood as the number of groups increases.  相似文献   
633.
In two experiments, we analyzed the use of intra‐group differentiation between normative and deviant members as an identity mobilization strategy in intergroup negotiations. Because ingroup members sometimes try to obtain the support of outgroup audiences to attain their goals, we propose that in intergroup negotiations, people attempt to minimize the distinction between the parties involved by changing the appraisal of deviance and including deviant members in the ingroup's prototype. In line with this hypothesis, differences in the assessment of typicality between normative and deviant targets were reduced in instrumental intergroup negotiation contexts. Furthermore, we explored a boundary condition for this effect and found that such outgroup approach is disrupted when threats taint the intergroup negotiation context. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
634.
The right and left visual fields each project to the contralateral cerebral hemispheres. The current study aimed to investigate the extent of the functional overlap of the two hemifields along the vertical meridian. We applied repetitive transcranial magnetic stimulation (rTMS) over the left and right occipital cortex to investigate whether the foveal representation of words is bilaterally represented or is split between the two hemispheres. Employing a lateralized lexical decision task, we first showed a double dissociation between the stimulated cortical site and performance; right visual field (RVF) but not left visual field (LVF) performance was impaired when the left visual cortex was stimulated, and LVF but not RVF performance was impairred when the right visual cortex was stimulated. Unilateral stimulation also significantly impaired lexical decision latencies to centrally presented words. These findings support the suggestion that foveal representation of words is split. We discuss future strategies for the use of TMS in further tests of the split representation account.  相似文献   
635.
Emerging technologies are increasingly used in an attempt to “enhance the human body and/or mind” beyond the contemporary standards that characterize human beings. Yet, such standards are deeply controversial and it is not an easy task to determine whether the application of a given technology to an individual and its outcome can be defined as a human enhancement or not. Despite much debate on its potential or actual ethical and social impacts, human enhancement is not subject to any consensual definition. This paper proposes a timely and much needed examination of the various definitions found in the literature. We classify these definitions into four main categories: the implicit approach, the therapy-enhancement distinction, the improvement of general human capacities and the increase of well-being. After commenting on these different approaches and their limitations, we propose a definition of human enhancement that focuses on individual perceptions. While acknowledging that a definition that mainly depends on personal and subjective individual perceptions raises many challenges, we suggest that a comprehensive approach to define human enhancement could constitute a useful premise to appropriately address the complexity of the ethical and social issues it generates.  相似文献   
636.
In this article, the Heidegger and Derrida controversy about the nature of questioning is revisited in order to rehabilitate questioning as an essential characteristic of contemporary philosophy. After exploring Heidegger's characterization of philosophy as questioning and Derrida's criticism of the primacy of questioning, we will evaluate Derrida's criticism and articulate three characteristics of Heidegger's concept of questioning. After our exploration of Heidegger's concept of questioning, we critically evaluate Heidegger's later rejection of questioning. With this, we not only contribute to the discussion about why Heidegger rejected questioning in his later thought and whether this rejection is legitimized, but also to the rehabilitation of questioning in contemporary philosophy.  相似文献   
637.
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639.
We investigated the discrimination of two neighboring intra- or inter-modal empty time intervals marked by three successive stimuli. Each of the three markers was a flash (visual—V) or a sound (auditory—A). The first and last markers were of the same modality, while the second one was either A or V, resulting in four conditions: VVV, VAV, AVA and AAA. Participants judged whether the second interval, whose duration was systematically varied, was shorter or longer than the 500-ms first interval. Compared with VVV and AAA, discrimination was impaired with VAV, but not so much with AVA (in Experiment 1). Whereas VAV and AVA consisted of the same set of single intermodal intervals (VA and AV), discrimination was impaired in the VAV compared to the AVA condition. This difference between VAV and AVA could not be attributed to the participants' strategy to perform the discrimination task, e.g., ignoring the standard interval or replacing the visual stimuli with sounds in their mind (in Experiment 2). These results are discussed in terms of sequential grouping according to sensory similarity.  相似文献   
640.
Executive function and intelligence are negatively associated with aggression, yet the role of executive function has rarely been examined in the context of school bullying. We studied whether different domains of executive function and non-verbal intelligence are associated with bullying involvement in early elementary school. The association was examined in a population-based sample of 1,377 children. At age 4 years we assessed problems in inhibition, shifting, emotional control, working memory and planning/organization, using a validated parental questionnaire (the BRIEF-P). Additionally, we determined child non-verbal IQ at age 6 years. Bullying involvement as a bully, victim or a bully-victim in grades 1–2 of elementary school (mean age 7.7 years) was measured using a peer-nomination procedure. Individual bullying scores were based on the ratings by multiple peers (on average 20 classmates). Analyses were adjusted for various child and maternal socio-demographic and psychosocial covariates. Child score for inhibition problems was associated with the risk of being a bully (OR per SD?=?1.35, 95%CI: 1.09–1.66), victim (OR per SD?=?1.21, 95%CI: 1.00–1.45) and a bully-victim (OR per SD?=?1.55, 95%CI: 1.10–2.17). Children with higher non-verbal IQ were less likely to be victims (OR?=?0.99, 95%CI: 0.98–1.00) and bully-victims (OR?=?95%CI: 0.93–0.98, respectively). In conclusion, our study showed that peer interactions may be to some extent influenced by children’s executive function and non-verbal intelligence. Future studies should examine whether training executive function skills can reduce bullying involvement and improve the quality of peer relationships.  相似文献   
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