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21.
Adolescent Substance Use: Preliminary Examinations of School and Neighborhood Context 总被引:1,自引:0,他引:1
Kevin W. Allison Isiaah Crawford Peter E. Leone Edison Trickett Alina Perez-Febles Linda M. Burton Ree Le Blanc 《American journal of community psychology》1999,27(2):111-141
In considering the influences of microsystems on adolescent substance use, familial and peer contexts have received the most extensive attention in the research literature. School and neighborhood settings, however, are other developmental contexts that may exert specific influences on adolescent substance use. In many instances, school settings are organized to provide educational services to students who share similar educational abilities and behavioral repertoires. The resulting segregation of students into these settings may result in different school norms for substance use. Similarly, neighborhood resources, including models for substance use and drug sales involvement, may play an important role in adolescent substance use. We briefly review literature examining contextual influences on adolescent substance use, and present results from two preliminary studies examining the contribution of school and neighborhood context to adolescent substance use. In the first investigation, we examine the impact of familial, peer, and school contexts on adolescent substance use. Respondents were 283 students (ages 13 to 18) from regular and special education classrooms in six schools. Although peer and parental contexts were important predictors of substance use, school norms for drug use accounted for variance in adolescent use beyond that explained by peer and parental norms. Data from a second study of 114 adolescents (mean age = 15) examines neighborhood contributions to adolescent substance use. In this sample, neighborhood indices did not contribute to our understanding of adolescent substance use. Implications for prevention are presented. 相似文献
22.
自控摄入小剂量酒精影响熟练驾驶行为的实验研究 总被引:1,自引:1,他引:0
一个小样本受试者内设计实验,受试者在实验允许的酒精剂量范围内自由选择摄入量。实验安排饮酒前,酒后30分钟、110分钟和170分钟四个测试阶段,分别检验受试者在模拟驾驶和实际驾驶两项任务中的认知行为。酒后30分钟实际驾驶的技能与其他三个测试期相比存在有意义的差别显著性;模拟测试任务中酒后对红、黄两种信号灯的认知反应时之间呈现显著性差别,酒后110分钟对黄色信号灯的反应明显延迟。研究提示:受试对酒精感受性的估计是不可靠的,小剂量酒精也能对驾驶行为构成伤害。 相似文献
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Individuals with trypophobia have an aversion towards clusters of roughly circular shapes, such as those on a sponge or the bubbles on a cup of coffee. It is unclear why the condition exists, given the harmless nature of typical eliciting stimuli. We suggest that aversion to clusters is an evolutionarily prepared response towards a class of stimuli that resemble cues to the presence of parasites and infectious disease. Trypophobia may be an exaggerated and overgeneralised version of this normally adaptive response. Consistent with this explanation, individuals with trypophobia, as well as comparison individuals, reported aversion towards disease-relevant cluster stimuli, but only the trypophobic group reported aversion towards objectively harmless cluster stimuli that had no relevance to disease. For both groups the level of aversion reported was predicted uniquely by a measure of disgust sensitivity. Scaled emotion ratings and open-ended responses revealed that the aversive response was predominantly based on the disease avoidance emotion, disgust. Many open-ended responses also described skin sensations (e.g. skin itching or skin crawling). These findings support the proposal that individuals with trypophobia primarily perceive cluster stimuli as cues to ectoparasites and skin-transmitted pathogens. 相似文献
26.
Grégoire S Rivalan M Le Moine C Dellu-Hagedorn F 《Neurobiology of learning and memory》2012,97(2):202-212
Concomitant deficits in working memory and behavioral inhibition in several psychiatric disorders like attention-deficit/hyperactivity disorder, addiction or mania, suggest that common brain mechanisms may underlie their etiologies. Based on the theoretical assumption that a continuum exists between health and mental disorders, we explored the relationship between working memory and inhibition in healthy individuals, through spontaneous inter individual differences in behavior, and tested the hypothesis of a functional link through the fronto-striatal dopaminergic system. Rats were classified into three groups, showing good, intermediate and poor working memory and were compared for their inhibitory abilities. These two functions were simultaneously modulated by a dose-effect of d-amphetamine and in situ hybridization was used to quantify dopaminergic receptor (RD1) mRNAs in prefrontal cortex and striatal areas. A functional relationship between working memory and inhibition abilities was revealed. Both functions were similarly modulated by d-amphetamine according to an inverted-U shaped relationship and depending on initial individual performances. D-amphetamine selectively improved working memory and inhibition of poor and intermediate performers at low doses whereas it impaired both processes in good performers at a higher dose. D1 receptors were less expressed in prelimbic, infralimbic and anterior cingulate cortices of good compared to intermediate and poor performers, whereas no difference was observed between groups in striatal areas. The synergy of working memory and inhibitory abilities, observed in both healthy and psychiatric populations, may originate from endogenous variability in dopaminergic prefrontal cortex activity. Such findings confirm the validity of a dimensional approach, based on the concept of continuity between health and mental disorders for identifying endophenotypes of mental disorders. 相似文献
27.
Lacombe D 《Journal international de bioéthique》2012,23(2):95-102, 178-9
28.
Two experiments examined how visuospatial processing engaged during text composition intervenes in memory for word location. Experiment 1 showed that in contrast to participants who performed a spatial task concurrently with composing a text, participants who performed a concurrent visual task recalled fewer word locations after the composition. Consequently, it is hypothesized that writers process the written text in order to visually represent its physical layout, and that this representation is then used when locating words. Experiment 2 tested this hypothesis by comparing a standard composition condition (with the written trace) with a condition in which the written trace was suppressed during composition, and with a condition without written trace and with added visual noise. Memory for word location only decreased with visual noise, indicating that construction of the visual representation of the text does not rely on the written trace but involves visual working memory. 相似文献
29.
The study evaluated the reliability of pass and fail classifications for several teacher certification tests. Since these tests are used in the context of a cut score to classify examinees as pass and fail, evaluating the accuracy and consistency of these classifications is important. The classification accuracy and consistency statistics were estimated using the RELCLASS software. Results indicated the following. (1) The 29 teacher certification tests that were examined had a relatively high classification accuracy (0.827 to 0.999) and consistency (0.760 to 0.999). (2) Both classification accuracy and consistency increased as the difference between the mean and cut score increased. (3) Classification accuracy and consistency was higher for multiple-choice (MC) as compared to tests consisting of only constructed-response (CR) items or a combination of CR and MC items. 相似文献
30.
Child care studies that have examined links between teachers' qualifications and children's outcomes often ignore teachers' and children's transitions between classrooms at a center throughout the day and only take into account head teacher qualifications. The objective of this investigation was to examine these traditional assumptions and to compare inferences made from these traditional models to methods accounting for transitions between classrooms and multiple teachers in a classroom. The study examined the receptive language, letter-word identification, and passage comprehension skills of 307 children enrolled in 49 community-based childcare centers serving primarily low-income families in Colorado. Results suggest that nearly one-third of children and over 80% of teachers moved daily between classrooms. Findings also reveal that failure to account for daily transitions between classrooms can affect interpretations of the relationship between teacher qualifications and child outcomes, with the model accounting for movement providing significant improvements in model fit and inference. 相似文献