镜像神经在药物心理渴求中的作用及机制

心理渴求是物质依赖者希望重新感受神经活性药物效应的渴望,其神经机制的早期影像研究,主要集中在前额皮质和奖赏中枢.镜像神经是新近发现的位于动作脑区,能理解、分析所观察动作的目的和性质,并通过内隐模拟,产生直接映射式的情绪和认知的神经.最新的研究发现尼古丁成瘾者在相关线索的刺激下,其镜像神经也能被激活.本研究旨在探索镜像神经参与相关线索下心理渴求形成的机制,为发展更可靠的依赖行为的生物学标记提供另一个重要目标,帮助人们更好地理解药物渴求形成的神经生物学基础与过程.     

Tobacco Use and Health in Young Adulthood

In this prospective longitudinal study, the authors investigated the association between lifetime tobacco use and subsequent health problems by age 30. The authors interviewed a community group of 749 participants from upstate New York at mean ages of 14, 16, 22, and 27 years. Daily tobacco use during any of the time periods, as well as the number of periods of daily tobacco use, were significantly associated with increased risk for respiratory ailments, neurobehavioral and cognitive problems, and general malaise. The results suggested that daily tobacco use, either during childhood, adolescence, the early 20s, or a combination of those times, predicted health problems by age 30. Effective smoking prevention programs that begin in childhood are imperative to prevent the occurrence of later health problems.     

Metaphysical Infinitism and the Regress of Being

This article offers a limited defense of metaphysical “infinitism,” the view that there are, or might be, infinite chains of ontological dependence. According to a widespread presupposition, there must be an ultimate ground of being—most likely, a plurality of fundamental atoms. Contrary to this view, this article shows that metaphysical infinitism is internally coherent. In particular, a parallel with the debate concerning infinitism about epistemic justification is suggested, and an “emergence model” of being is put forward. According to the emergence model, the being of any given entity gradually arises out of an infinite series of progressively less dependent entities—it is not wholly transmitted, as it were, from a basic, ungrounded level to all the dependent ones in a step‐by‐step fashion. Some objections are considered and rebutted.     

Direction of dependence in measurement error models

Methods to determine the direction of a regression line, that is, to determine the direction of dependence in reversible linear regression models (e.g., x→y vs. y→x), have experienced rapid development within the last decade. However, previous research largely rested on the assumption that the true predictor is measured without measurement error. The present paper extends the direction dependence principle to measurement error models. First, we discuss asymmetric representations of the reliability coefficient in terms of higher moments of variables and the attenuation of skewness and excess kurtosis due to measurement error. Second, we identify conditions where direction dependence decisions are biased due to measurement error and suggest method of moments (MOM) estimation as a remedy. Third, we address data situations in which the true outcome exhibits both regression and measurement error, and propose a sensitivity analysis approach to determining the robustness of direction dependence decisions against unreliably measured outcomes. Monte Carlo simulations were performed to assess the performance of MOM-based direction dependence measures and their robustness to violated measurement error assumptions (i.e., non-independence and non-normality). An empirical example from subjective well-being research is presented. The plausibility of model assumptions and links to modern causal inference methods for observational data are discussed.     

On the explaining‐away phenomenon in multivariate latent variable models

Many probabilistic models for psychological and educational measurements contain latent variables. Well‐known examples are factor analysis, item response theory, and latent class model families. We discuss what is referred to as the ‘explaining‐away’ phenomenon in the context of such latent variable models. This phenomenon can occur when multiple latent variables are related to the same observed variable, and can elicit seemingly counterintuitive conditional dependencies between latent variables given observed variables. We illustrate the implications of explaining away for a number of well‐known latent variable models by using both theoretical and real data examples.     

Concurrent alcohol and tobacco use among school-going adolescents in Namibia: Prevalence and risk factors

The aim of this study was to investigate the prevalence and risk factors for concurrent alcohol and tobacco use among school-going adolescents in Namibia. Data were from a sample of 4 531 Namibian middle school children (females = 53.1%; mean age = 15.8 years, SD = 1.8 years). They completed the Namibia Global School-based Student Health Survey (GSHS) in 2013. Overall, 74.4% of alcohol users in the past month were frequent tobacco users; whereas 40.5% of tobacco users in the past month were frequent alcohol users. Compared to students who were neither alcohol nor tobacco users (63.1%), concurrent alcohol and tobacco users were more likely to self-report with a lack of parent support, to have used illicit drugs, to have engaged in school truancy, to be sedentary in behaviour, to have engaged in a physical fight, and to have had two or more sexual partners. Substance use prevention and treatment programmes with adolescents should routinely address their risk for comorbid tobacco and alcohol use.     

Examining the structure of emotional intelligence at the item level: New perspectives,new conclusions

Despite twenty years of research, many unknowns remain regarding the Mayer–Salovey (e.g., 1997) model of emotional intelligence (EI) and the validity of tests that have been designed to measure it. Evidence relevant to the internal structure of EI has come mainly from factor-analytic studies of the MSCEIT and the MEIS, utilising parcelled task scores rather than individual test items. This approach has several deficiencies: in addition to the loss of item-level information, it results in an insufficient number of observed variables per factor and an inability to separate structural sources of local item dependence (i.e., method variance) from construct-related variance. The present study (N=707) employed multidimensional item response modelling to investigate the dimensional structure of the MSCEIT, at the item level, for the first time. It is shown that item format and the specific choice of task explain far more of the variance in response patterns than does the hypothesised dimensional structure of EI, to the point that there is no empirical reason to prefer a higher-dimensional model of EI over a unidimensional model. It is argued that the advantage of an item-level perspective can be fundamental, rather than merely incremental.     

An Alternate Method of Deriving Priorities and Related Inferences for Group Decision Making in Analytic Hierarchy Process

Some work has been carried out in the past on statistically deriving priorities in Analytic Hierarchy Process (AHP). In AHP, the aggregated worths of the alternatives, when compared with respect to several criteria, are estimated in a hierarchical comparisons model introduced by Saaty. In this setup, statistical models are used for Saaty's method of scaling in paired comparisons experiments in any level of the hierarchy. At the end, the final priority weights of the alternatives and related inferences are developed with appropriate statistical methods. Existing statistical methods in the literature assume independence of the entries of the paired comparison matrix. However, these entries are highly dependent among themselves. In this article, we propose a statistical method that allows for the dependence among the entries of the pairwise comparisons matrix. The proposed method is then illustrated with a numerical example. Copyright © 2011 John Wiley & Sons, Ltd.