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981.
Ridenour, Daley, & Reich (2000) suggest that the Family Assessment Device should be reorganized. We disagree and provide further reasons why such a reorganization is unwise.  相似文献   
982.
Preschool boys' emotional displays during conflicts with mixed-sex peers were related to individual differences in peer sociometric status and teacher ratings of disruptive behavior. Participants were 60 4- to 5-year old boys from low-income families who were videotaped with a small group of classmates in a Head Start preschool classroom. Conflicts were identified and emotional displays were coded from videotape. Results indicated that conflicts were more negative in emotional tone at the end than at the beginning of the year. Furthermore, children tended to mirror each others' emotional displays at the end but not the beginning of the preschool year. In addition, gleeful taunting, a form of emotional aggression, more strongly predicted negative peer nominations and teacher ratings than anger, suggesting that anger may be a more socially accepted form of emotional expression during conflicts among preschool-age children. Implications and directions for future research and interventions are discussed.  相似文献   
983.
A. G. Greenwald, M. R. Klinger, and E. S. Schuh (1995) investigated subliminal perception using a regression-based test for a dissociation between direct and indirect measures of perceptual ability. Direct and indirect measures were obtained for each observer, and a regression analysis was used to predict the amount of indirect perception at the point where the direct measure showed zero sensitivity. A significant positive intercept, obtained with both standard regression and a modified regression developed by K. C. Klauer, S. C. Draine, and A. G. Greenwald (1998), was used to argue for the key dissociation. When the assumptions of these methods are not met, however, simulations indicate that significant positive intercepts can often be obtained even if there is no dissociation. Moreover, the assumptions are theoretically implausible and inconsistent with some aspects of the results. Thus, the significant positive intercept is not strong evidence of the key dissociation.  相似文献   
984.
When location-relevant trials with an incompatible spatial stimulus-response mapping are mixed with location-irrelevant trials, responses on the latter trials are faster when stimulus and response locations do not correspond than when they do. Experiments 1 and 2 showed that this reverse “Simon effect” also occurs when the location information is presented verbally or symbolically on both location-relevant and location-irrelevant trials. The reversal was absent, however, in conditions of Experiments 1–3 in which the mode of presentation was different on the location-relevant trials than on the location-irrelevant trials. Experiment 4 demonstrated that differences in physical characteristics between the location-relevant and location-irrelevant stimuli were not sufficient to eliminate the reverse Simon effect. These findings imply that the short-term associations between stimulus location information and responses defined for the location-relevant task are relatively mode specific. Received: 21 December 1999 / Accepted: 26 April 2000  相似文献   
985.
A defined genetic syndrome with neurobehavioral components offers an unusual paradigm for the correlation of genetic defects with neurodevelopmental abnormalities. The power of the combination of detailed behavioral, neuroanatomical, and genetic studies has been demonstrated in studies of other conditions involving the sex chromosomes, such as Fragile X syndrome (Mazzocco [2000] Ment Retard Develop Disabil Res Rev. 6:96-106) and Turner syndrome (Ross [2000] Ment Retard Develop Disabil Res Rev. 6:135-141). Although the behavioral and neurologic difficulties that have been identified in Klinefelter syndrome (KS) are in most cases milder than the consequences of many other genetic syndromes, the deficits in KS cause significant morbidity, representing a more common, but poorly understood, subtype of those with learning disabilities. Both as children and as adults, KS subjects appear to offer a powerful genetic model for the study of language and language-based learning disabilities. Although it has been proposed that the language-based learning difficulties of KS boys are similar to those of nonaneuploidic dyslexics [Bender et al., 1986; Geschwind et al., 1998], this is not yet well established. The co-morbid frontal-executive dysfunction observed in KS is also a likely contributor to learning difficulties and, perhaps, social cognition, in many KS patients. It is also proposed that altered left-hemisphere functioning, whether causing, or due to, altered functional and anatomical cerebral dominance, is at the core of KS subjects' language problems. Although X chromosomal loci can provide only part of the picture, the study of KS subjects, a population with a relatively homogeneous etiology for dyslexia/dysphasia and frontal-executive dysfunction, offers many advantages over such a study in the general population, in which both dyslexia and attentional disorders are quite genetically heterogeneous [Decker and Bender, 1988; Pennington, 1990; Grigorenko et al., 1997; Geschwind et al., 1998]. Furthermore, the interaction of genetic factors and hormonal influences in the cognitive phenotypes described remains an unexplored area for future investigation. MRDD Research Reviews 2000;6:117-124.  相似文献   
986.
This paper discusses the National Bioethics Advisory Commission's (NBAC's) report on research involving persons with mental disorders that may affect decisionmaking capacity. After placing the NBAC recommendations into their historic context, the authors propose a strategy to enroll decisionally incapacitated subjects into neuropsychiatric research. The authors maintained that their proposed consensus model for research authorization, utilizing subject advocates, fosters valuable clinical research while protecting potentially vulnerable subjects.  相似文献   
987.
Three experiments using psychological refractory period (PRP) tasks documented backward crosstalk effects in which the nature of the second-task response influenced the first-task response latencies. Such effects are difficult to explain within currently popular bottleneck models, according to which second-task response selection does not begin until first-task response selection has finished. In Experiments 1 and 2, the first of the PRP tasks required a choice reaction time (RT) response, whereas the second task required a go/no-go decision. Task 1 responses were faster when the second task required a go response than when it required a no-go response. Experiment 3 showed that Task 1 RTs were also influenced by the complexity of second-task responses. These backward crosstalk effects indicate that significant second-task processing is carried out in time to influence first-task responses and thus challenge strictly serial bottleneck models.  相似文献   
988.
To examine public opinion regarding the effectiveness of means restriction as an approach to preventing suicide we asked a national sample of 2,770 respondents a hypothetical question about what effect a suicide barrier might have had on the ultimate fate of the more than 1,000 people who have jumped to their death from the Golden Gate Bridge. Thirty-four percent of respondents believed that every single jumper would have found another way to complete suicide and an additional 40% believed that "most" would have completed suicide using other means. The strongest predictors of belief in complete substitution were firearm ownership and cigarette smoking. Belief in the inevitability of suicide may be a political impediment to adopting potentially effective suicide prevention efforts.  相似文献   
989.
This study compared adults (Homo sapiens), young children (Homo sapiens), and adult tamarins (Saguinus oedipus) while they discriminated global and local properties of stimuli. Subjects were trained to discriminate a circle made of circle elements from a square made of square elements and were tested with circles made of squares and squares made of circles. Adult humans showed a global bias in testing that was unaffected by the density of the elements in the stimuli. Children showed a global bias with dense displays but discriminated by both local and global properties with sparse displays. Adult tamarins' biases matched those of the children. The striking similarity between the perceptual processing of adult monkeys and humans diagnosed with autism and the difference between this and normatively developing human perception is discussed.  相似文献   
990.
In 2 experiments, the authors investigated whether age-related differences exist in metacomprehension by evaluating predictions based on the ease-of-processing (EOP) hypothesis. According to this hypothesis, judgments of how well a text has been learned are based on how easily each text was processed; easier processing results in higher judgments. Participants read either sentence pairs or longer texts and judged their learning of each immediately afterward. Although an age-related difference in the use of processing ease in judgments was observed with sentence pairs, for longer texts older and younger adults' judgments were similarly related to processing ease. In both experiments, age equivalence was also evident in the accuracy of the judgments at predicting performance on the criterion test. The overall pattern of results suggests that judging text learning remains largely intact with aging.  相似文献   
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