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941.
Human beings with diminished decision-making capacities are usually thought to require greater protections from the potential harms of research than fully autonomous persons. Animal subjects of research receive lesser protections than any human beings regardless of decision-making capacity. Paradoxically, however, it is precisely animals’ lack of some characteristic human capacities that is commonly invoked to justify using them for human purposes. In other words, for humans lesser capacities correspond to greater protections but for animals the opposite is true. Without explicit justification, it is not clear why or whether this should be the case. Ethics regulations guiding human subject research include principles such as respect for persons—and related duties—that are required as a matter of justice while regulations guiding animal subject research attend only to highly circumscribed considerations of welfare. Further, the regulations guiding research on animals discount any consideration of animal welfare relative to comparable human welfare. This paper explores two of the most promising justifications for these differences␣between the two sets of regulations. The first potential justification points to lesser moral status for animals on the basis of their lesser capacities. The second potential justification relies on a claim about the permissibility of moral partiality as␣found in common morality. While neither potential justification is sufficient to justify the regulatory difference as it stands, there is possible common ground between supporters of some regulatory difference and those rejecting the current difference.  相似文献   
942.
Chen H  Jackson T  Huang X 《Body image》2006,3(4):401-412
This research presents four studies on the initial development and validation of the 48-item Negative Physical Self Scale (NPS), a multidimensional measure of body image concerns for use with Chinese samples. In Study 1 (N = 1095), exploratory factor analyses identified five dimensions underlying the NPS (General Appearance, Facial Appearance, Shortness, Fatness, Thinness). In Study 2 (N = 1057), confirmatory factor analyses replicated this factor structure. In Studies 3 and 4, the validity of all NPS dimensions except Thinness Concern was supported via their patterns of relation with both objective physical characteristics/behaviors and other self-report measures of body image and general self worth. Because Chinese adolescents and young adults expressed relatively more concerns about General Appearance, Shortness, and Facial Appearance than about Fatness, the NPS may have greater utility for assessing body image disturbances in China than existing measures that focus exclusively on general body satisfaction and body size/weight.  相似文献   
943.
This study investigated DSM-defined anxiety symptoms in South African youths. Children and adolescents (N = 701) from various cultural groups completed the SCARED and a questionnaire measuring perceived parental rearing behaviors. Results indicated that the psychometric properties of the SCARED were satisfactory in the total sample of South African youths, and acceptable in colored and black children and adolescents. Further, colored and black youths displayed higher SCARED scores than white youths, and there were also differences in the perceived parental rearing behaviors of the cultural groups. White youths generally rated their parents' rearing behaviors as less anxious, overprotective, and rejective, but more emotionally warm than colored and black youths. Finally, positive correlations were found between anxious rearing, overprotection, and rejection and anxiety symptoms. The clinical and research implications of these findings are briefly discussed.  相似文献   
944.
Phonological deficits in dyslexia are typically assessed using metalinguistic tasks vulnerable to extraneous factors such as attention and memory. The present work takes the novel approach of measuring phonology using eyetracking. Eye movements of dyslexic children were monitored during an auditory word recognition task in which target items in a display (e.g., candle) were accompanied by distractors sharing a cohort (candy) or rhyme (sandal). Like controls, dyslexics showed slower recognition times when a cohort distractor was present than in a baseline condition with only phonologically unrelated distractors. However, unlike controls, dyslexic children did not show slowed recognition of targets with a rhyme distractor, suggesting they had not encoded rhyme relationships. This was further explored in an overt phonological awareness test of cohort and rhyme. Surprisingly, dyslexics showed normal rhyme performance but poorer judgment of initial sounds on these overt tests. The results implicate impaired knowledge of rhyme information in dyslexia; however they also indicate that testing methodology plays a critical role in how such problems are identified.  相似文献   
945.
This article reports on a series of 5 analyses of spontaneous production of verbal inflection (tense and person–number agreement) by 2-year-olds acquiring French as a native language. A formal analysis of the qualitative and quantitative results is developed using the unique resources of Optimality Theory (OT; Prince & Smolensky, 2004). It is argued that acquisition of morphosyntax proceeds via overlapping grammars (rather than through abrupt changes), which OT formalizes in terms of partial rather than total constraint rankings. Initially, economy of structure constraints take priority over faithfulness constraints that demand faithful expression of a speaker's intent, resulting in child production of tense that is comparable in level to that of child-directed speech. Using the independent Predominant Length of Utterance measure of syntactic development proposed in Vainikka, Legendre, and Todorova (1999), production of agreement is shown first to lag behind tense then to compete with tense at an intermediate stage of development. As the child's development progresses, faithfulness constraints become more dominant, and the overall production of tense and agreement becomes adult-like.  相似文献   
946.
Go/no-go tasks seem to provide a simple marker of inhibitory development in young children. Children are told to respond to one stimulus on go trials but to make no response to another stimulus on no-go trials; responding on no-go trials is assumed to reflect a failure to inhibit the go response. However, there is evidence to suggest that a type of go/no-go task, which we call the "button-press" task, does not require inhibition. We investigated the conditions under which young children (M=3 years 6 months, N=120) experience inhibitory difficulty with this type of task. The data suggest that the speed of stimulus presentation is crucial and that other studies using this type of task have presented the stimuli too briefly. The importance of establishing the inhibitory credentials of a task before it is used as a marker of inhibitory control is emphasized.  相似文献   
947.
This research explores the way in which young children (5 years of age) and adults use perceptual and conceptual cues for categorizing objects processed by vision or by audition. Three experiments were carried out using forced-choice categorization tasks that allowed responses based on taxonomic relations (e.g., vehicles) or on schema category relations (e.g., vehicles that can be seen on the road). In Experiment 1 (visual modality), prominent responses based on conceptually close objects (e.g., objects included in a schema category) were observed. These responses were also favored when within-category objects were perceptually similar. In Experiment 2 (auditory modality), schema category responses depended on age and were influenced by both within- and between-category perceptual similarity relations. Experiment 3 examined whether these results could be explained in terms of sensory modality specializations or rather in terms of information processing constraints (sequential vs. simultaneous processing).  相似文献   
948.
This study compared nonverbal numerical processing in 6-year-olds with that in nonhuman animals using a numerical bisection task. In the study, 16 children were trained on a delayed match-to-sample paradigm to match exemplars of two anchor numerosities. Children were then required to indicate whether a sample intermediate to the anchor values was closer to the small anchor value or the large anchor value. For two sets of anchor values with the same ratio, the probability of choosing the larger anchor value increased systematically with sample number, and the psychometric functions superimposed when plotted on a logarithmic scale. The psychometric functions produced by the children also superimposed with the psychometric functions produced by rhesus monkeys in an analogous previous experiment. These examples of superimposition demonstrate that nonverbal number representations, even in children who have acquired the verbal counting system, are modulated by Weber's law.  相似文献   
949.
The experiments described in the lead articles by Kowalski and Zimiles and by O'Hanlon and Roberson examine factors that lead to color term acquisition. These experiments touch on the debate regarding the relative contributions of language and concepts in word learning. In this reflection, we examine how conclusions concerning the debate depend deeply on the particular task presented to children, and we propose an alternative approach to studying color term acquisition.  相似文献   
950.
Previous research has emphasized the role of within-match similarity in children's comparisons. The current study investigated another potentially important contributing factor, namely the distinctiveness of the matching items relative to other items in the scene. Using a well-known relational mapping task, we found that 3- and 4-year-olds made more correct matches between identical objects when those objects were maximally distinctive from the foils. In a cross-mapping experiment, where same relative size was pitted against object similarity, 3-year-olds made more incorrect object matches when the objects were both similar to each other and distinctive from the foils. Furthermore, 3- and 4-year-olds performed the same, regardless of within-match similarity, so long as the ratios of within-match and nonmatch similarity were roughly equal. These findings suggest that children's comparisons are guided by a ratio consisting of many pairwise similarity relations, including (but not limited to) the degree of within-match similarity.  相似文献   
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