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211.
This essay will address the ethical issues that have emerged in the first considerations of the newly emerging stem cell technology. Many of us in the field of bioethics were deliberating related issues as we first learned of the new science and confronted the ethical issues it raised. In this essay, I will draw on the work of colleagues who were asked to reflect on the early stages of the research (members of the IRBs, the Geron Ethicist Advisory Board, and the National Bioethics Advisory Commission) as the field debated the issues of consent, moral status, use of animal tissues, abortion, use of fetal tissue, and the nature and goals of entrepreneurial research. In this new capacity, ethicists weighed the problem of privacy, the role of justice considerations, and the issues of the marketplace in science. At this point, it is clear that far more issues remain unresolved than are settled, that there is largely unexplored territory ahead, and that the single most important task that faces us as a field is a steady call for ongoing conversation and public debate.  相似文献   
212.
Facilitation among morphologically related words generally is impervious to the prefixed or suffixed structure of primes and targets. A notable exception arises, however, when both primes and targets are suffixed. More specifically, when primes are auditory and targets are visual, facilitation for a suffixed target (e.g., payment) is absent when it follows a prime (e.g., payable) that is morphologically related and suffixed (Marslen-Wilson, Tyler, Waksler, & Older, 1994). To account for null facilitation (viz., the "suffix-suffix" effect), Marslen-Wilson and his colleagues posit inhibitory links between suffixes of morphological relatives. The present study assesses the generality of the "suffix-suffix" effect. When morphological facilitation is assessed relative to an orthographically related baseline, suffixed primes facilitate derivationally as well as inflectionally related morphological targets when primes are visual as well as auditory in both the lexical decision and naming tasks. The present findings call into question lexical models that posit inhibitory links between suffixes of morphological relatives.  相似文献   
213.
Around 1 year of age, infants develop the ability to individuate objects in the absence of spatiotemporal information. Some have proposed that this capacity relies on the emergence of language and, in particular, that comprehending an object's label is required to individuate it as a particular kind. One approach to testing this hypothesis is to conduct experiments on pre-linguistic human infants. A second is to test non-linguistic animals. We followed the second approach, exploring whether semi-free-ranging rhesus macaques can individuate objects using property/kind information. To make the results most directly comparable, we adapted a reaching paradigm used to examine property/kind individuation in infants. Results from three experiments demonstrate that, like 12-month-old infants, adult rhesus macaques can use both spatiotemporal and property/kind information to individuate food objects. In a fourth experiment designed to examine which properties are used to individuate food objects, results revealed that rhesus use color, but not shape. These results, together with experiments involving different procedures, provide support for the conclusion that in the absence of linguistic abilities, some non-human primates spontaneously use property/kind information to individuate objects.  相似文献   
214.
In this study, we use the association between various measures of the morphological family and decision latencies to reveal the way in which the components of Dutch and English compounds are processed. The results show that for constituents of concatenated compounds in both languages, a position-related token count of the morphological family plays a role, whereas English open compounds show an effect of a type count, similar to the effect of family size for simplex words. When Dutch compounds are written with an artificial space, they reveal no effect of type count, which shows that the differential effect for the English open compounds is not superficial. The final experiment provides converging evidence for the lexical consequences of the space in English compounds. Decision latencies for English simplex words are better predicted from counts of the morphological family that include concatenated and hyphenated but not open family members.  相似文献   
215.
Children with hydrocephalus decode words better than they understand what they read. We tested whether children with hydrocephalus (from myelomeningocele or aqueduct stenosis) (1) decode words slowly, (2) use decoding processes similar to those of neurologically intact peers, and (3) comprehend poorly to the extent that they are slow decoders. We compared speed of word decoding in 33 children with hydrocephalus and 33 controls matched on a pairwise basis for age, grade, and word decoding accuracy. The children with hydrocephalus were as fast as controls in reading words, but, unlike controls, they did not demonstrate an effect of spelling-sound regularity. Further, decoding speed did not contribute to reading comprehension beyond word decoding accuracy. The reading comprehension deficits of good decoders with hydrocephalus are not related to early-stage processing deficits in word recognition speed. Likely origins of comprehension failure in this group are discussed.  相似文献   
216.
Behavioral and cognitive–behavioral strategies, including exposure, social skills training, and peer-mediated approaches, used to treat childhood shyness and related impairments are described. In addition, relevant outcome studies published within the past 20 years are evaluated, and limitations regarding the generalization, maintenance, and social validity of the reported treatment gains are addressed. Although the interventions reviewed have demonstrated short-term merit in ameliorating social and emotional impairments, such as problematic peer relations and internalizing difficulties, there currently is a lack of evidence to support the social validity and long-term generalization and maintenance of such behavioral gains. Thus, recommendations for future research are made, including the need to (a) assess the social validity of treatment outcomes, (b) utilize important socialization agents (e.g., parents, teachers, peers), and (c) conduct prevention research and longitudinal outcome studies.  相似文献   
217.
Northern Ireland remains both one of the more religiously active and also one of the most religiously divided countries in Europe. In this context 1,093 sixth-form pupils attending Protestant schools and 1,266 sixth-form pupils attending Catholic schools (aged between 16 and 19 years) completed the abbreviated Eysenck Personality Questionnaire Revised (EPQR-A), as a measure of psychological health, alongside the Francis Scale of Attitude toward Christainity (FSAC). The findings demonstrated that a positive attitude toward Christianity was associated with neither higher nor lower neuroticism scores, but was associated in both religious communities with lower psychoticism scores. There is no evidence, therefore, to associate a positive view of Christianity with poorer levels of psychological health among adolescents in Northern Ireland, and some evidence to associate a positive view of Christianity with better levels of psychological health.  相似文献   
218.
Recent literature has emphasized the need to examine executive functions (EF) in children using multiple sources, including both parent rating and performance-based measures. Computerized Go/No-Go tests, including commercially available continuous performance tests (CPTs), represent one of the most commonly used methods of assessing inhibitory control - a variable central to the executive function construct. We examined the relationship between parent ratings of inhibitory control and CPT performance in two mixed clinical samples. Experiment 1 examined 109 children ages 6-18 using the Behavior Rating Inventory of Executive Function (BRIEF; Gioia, Isquith, Guy, & Kenworthy, 2000) and the Conners' CPT-II (Conners, 2000). In this sample, ratings on the BRIEF Inhibit scale (mean T-score = 62.3) were significantly higher than the CPT-II commissions score (mean T-score = 50.7; p < .0001); and the BRIEF and CPT-II scores were not highly correlated (r = - .12). Experiment 2 examined a sample of 131 children ages 7-18 using the BRIEF and the Tests of Variables of Attention (TOVA; Greenberg, 1996). In this sample, parent ratings on the BRIEF Inhibit scale (mean T-score = 56.8) were similar to TOVA commissions scores (mean T-score = 58.6; p = .33), although still poorly correlated (r = -.02). Factor analyses exploring covariance between BRIEF scales CPT-II variables (Experiment 1) and between BRIEF and TOVA (Experiment 2) yielded similar findings. In both experiments, all eight BRIEF scales loaded on a single factor, with no overlap with either the CPT-II or the TOVA. In mixed outpatient clinical samples, the BRIEF appears to measure different elements of inhibitory control than those assessed by computerized continuous performance tests.  相似文献   
219.
220.
This study examined the effect of divided attention (DA) on global judgment of learning (JOL) accuracy in a multitrial list learning paradigm. A word monitoring task was used to divide attention. Participants were assigned to an attention condition (DA at encoding, DA at judgment, DA at retrieval, or focused attention) and completed 4 learning trials, each comprising a study, judgment, and recall phase. Participants showed greater overconfidence in the DA at encoding (Trial 2) and DA at retrieval (Trials 1 and 2) conditions than in the focused attention condition. DA atjudgment did not affect JOL accuracy, and there was no effect of DA in Trials 3 and 4 on JOL accuracy across all attention conditions. Results indicate that participants consider conditions of encoding and retrieval but do not engage in recall when forming global JOLs. These findings suggest that people rely on extrinsic cues when making repeated, global metamemoryjudgments.  相似文献   
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