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101.
102.
Infants aged 3-5 months (mean of approximately 4 months) were given a novel anticipatory looking task to test object permanence understanding. They were trained to expect an experimenter to retrieve an object from behind a transparent screen upon hearing a cue ("Doors up, here comes the hand"). The experimenter then hid the object behind one of two opaque screens and after either 2 or 8s gave the "doors up" cue. Infants looked to the correct location after the two-second delay, but not after the eight-second delay. This indicates a brief memory that the object is present behind the occluder. The study provides converging evidence that infants grasp object permanence by a young age. The novel anticipatory looking paradigm helps rule out counter-explanations applied to violation-of-expectation tasks. 相似文献
103.
The effects of universal pre-K on cognitive development 总被引:2,自引:0,他引:2
In this study of Oklahoma's universal pre-K program, the authors relied on a strict birthday eligibility criterion to compare "young" kindergarten children who just completed pre-K to "old" pre-K children just beginning pre-K. This regression-discontinuity design reduces the threat of selection bias. Their sample consisted of 1,567 pre-K children and 1,461 kindergarten children who had just completed pre-K. The authors estimated the impact of the pre-K treatment on Woodcock-Johnson Achievement test scores. The authors found test impacts of 3.00 points (0.79 of the standard deviation for the control group) for the Letter-Word Identification score, 1.86 points (0.64 of the standard deviation of the control group) for the Spelling score, and 1.94 points (0.38 of the standard deviation of the control group) for the Applied Problems score. Hispanic, Black, White, and Native American children all benefit from the program, as do children in diverse income brackets, as measured by school lunch eligibility status. The authors conclude that Oklahoma's universal pre-K program has succeeded in enhancing the school readiness of a diverse group of children. 相似文献
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105.
This article presents an account of job discrimination according to which people redefine merit in a manner congenial to the idiosyncratic credentials of individual applicants from desired groups. In three studies, participants assigned male and female applicants to gender-stereotypical jobs. However, they did not view male and female applicants as having different strengths and weaknesses. Instead, they redefined the criteria for success at the job as requiring the specific credentials that a candidate of the desired gender happened to have. Commitment to hiring criteria prior to disclosure of the applicant's gender eliminated discrimination, suggesting that bias in the construction of hiring criteria plays a causal role in discrimination. 相似文献
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107.
This study examined cognitive processing speed through four modalities (auditory-verbal, visual-verbal, visual, and visual-visual) at the end of Grade 1 and how it influences reading and spelling. The subjects were 124 French-speaking children, selected for their contrasting performance on reading and spelling tasks. The children in the first group (N=69) were average readers; the second group of children (N=55) performed worse or much worse on all reading and spelling tasks. The experimental design consisted of a set of 10 tasks administered in two sessions. The major findings reveal that: (1) the children with reading difficulties displayed low and slow performance on most cognitive tasks, whatever the modality; (2) auditory-verbal and visual-verbal processing speed significantly predicted written language, which was not the case with the visual modalities; and (3) that visual problems did not appear to be a potential cause of reading problems in most delayed readers. The findings also confirm the independence of phonological and naming-speed skills in reading development and reading impairment. 相似文献
108.
Responses to the 1999 Youth Risk Behavior Survey including suicide ideation, attempt, medically treated attempt, and six problem behaviors were analysed. Youth across the spectrum ideated. Overwhelmingly, the 17% of youth with more than three problem behaviors were the youth who acted; they accounted for 60% of medically treated suicidal acts. Compared to adolescents with zero problem behaviors, the odds of a medically treated suicide attempt were 2.3 times greater among respondents with one, 8.8 with two, 18.3 with three, 30.8 with four, 50.0 with five, and 227.3 with six. A count of problem behaviors offers a reliable way to identify suicide risk. 相似文献
109.
Crawford TN Cohen P Johnson JG Kasen S First MB Gordon K Brook JS 《Journal of personality disorders》2005,19(1):30-52
Approximately 800 youths from the Children in the Community Study (Cohen & Cohen, 1996) have been assessed prospectively for over 20 years to study personality disorders (PDs) in adolescents and young adults. In this article we evaluate the Children in the Community Self-Report (CIC-SR) Scales, which were designed to assess DSM-IV PDs using self-reported prospective data from this longitudinal sample. To evaluate convergent validity, we assessed concordance between the CIC-SR Scales and the Structured Clinical Interview for DSM-IV Personality Disorders (SCID-II; First, Gibbon, Spitzer, Williams, & Benjamin, 1995) in 644 participants at mean age 33. To assess predictive validity, we used CIC-SR Scales at mean age 22 to predict subsequent CIC-SR and SCID-II Personality Questionnaire scores at mean age 33. In these analyses the CIC-SR Scales matched or exceeded benchmarks established in previous comparisons between self-report instruments and structured clinical interviews. Unlike other self-report scales, the CIC-SR did not appear to overestimate diagnoses when compared with SCID-II clinical diagnoses. 相似文献
110.
Developing human-nonhuman chimeras in human stem cell research: ethical issues and boundaries 总被引:1,自引:0,他引:1
The transplantation of adult human neural stem cells into prenatal non-humans offers an avenue for studying human neural cell development without direct use of human embryos. However, such experiments raise significant ethical concerns about mixing human and nonhuman materials in ways that could result in the development of human-nonhuman chimeras. This paper examines four arguments against such research, the moral taboo, species integrity, "unnaturalness," and human dignity arguments, and finds the last plausible. It argues that the transfer of human brain or retinal stem cells to nonhuman embryos would not result in the development of human-nonhuman chimeras that denigrate human dignity, provided such stem cells are dissociated. The article provides guidelines that set ethical boundaries for conducting such research that are consonant with the requirements of human dignity. 相似文献