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961.
To be pertinent to democratic practice, collective choice functions need not apply to all possible constellations of individual preference, but only to those that are humanly possible in an appropriate sense. The present paper develops a theory of humanly possible preference within the context of the mathematical theory of learning. The theory of preference is then exploited in an attempt to resolve Arrow's voting paradox through restriction of the domain of majoritarian choice functions. 相似文献
962.
Separate verbal memory and naming deficits in attention deficit disorder and reading disability 总被引:4,自引:0,他引:4
In this study, verbal memory and naming abilities were investigated in reading disabled (RD) and control children who were characterized according to the presence or absence of attention deficit disorder (ADD). Results indicate that deficits in learning and memory for recently acquired information occur as a function of ADD rather than RD while deficits in naming are specific to RD rather than ADD. We conclude that ADD is a major source of additional and separate cognitive morbidity in RD children. 相似文献
963.
Comprehension of connected language as assessed by the Revised Token Test (RTT) was studied in 17 children with left hemisphere lesions (LL) and 11 with right hemisphere lesions (RL). LL children's significantly lower performance on several subtests than left controls (LC) matched by age, sex, race, and social class appeared to be related to the memory demands of these subtests rather than the limited syntactic elements assessed by the RTT. LL subjects requested significantly more command repetitions than control or RL subjects and when a repetition was not requested LL subjects often responded with immediacy. Although RL children tended to perform lower than right matched controls (RC), these differences were not significant nor readily related to either the memory or specific linguistic structures assessed. RL subjects required fewer command repetitions than LL subjects and exhibited a significantly greater frequency of immediate responses than controls or LL subjects. While based on few children, a trend for LL children with retrorolandic lesions to perform more poorly than those with left prerolandic lesions was suggested. No systematic difference in performance was apparent for children with left cortical vs. left subcortical lesions or among discrete sites of lesions within the right hemisphere. Children with left lesions prior to 1 year of age performed no better and, in several instances, significantly poorer than LL patients sustaining lesions after 1 year of age. Among RL subjects, those sustaining lesions after 1 year of age had greater difficulty than those with lesion onset before 1 year of age, especially on linguistic elements which seemed to be dependent upon visual spatial properties. Further studies are needed to evaluate the comprehension of more complex linguistic structures among children with unilateral brain lesions as well as to study the role of more basic factors such as memory and attention in explaining the present findings. 相似文献
964.
Laurence B. Leonard Letizia Sabbadini Jeanette S. Leonard Virginia Volterra 《Brain and language》1987,32(2):233-252
A common profile in English-speaking specifically language-impaired children is a moderate deficit across a broad range of linguistic features and a more marked, selective impairment in using bound morphemes and components of the verb system. To gain a clearer understanding of the nature of these more serious problems, we examined the speech of monolingual Italian-speaking as well as English-speaking children with specific language impairment. The evidence suggested that phonological factors contributed significantly to these children's extraordinary problems with particular linguistic features. Contrary to expectations, other marked deficits seemed more related to the opacity of the rules involved and homonymity with other morphemes than to problems with formal grammatical devices in general or components of the verb system in particular. 相似文献
965.
Regional cerebral blood flow (rCBF) may be measured with inhalation techniques that use end-expired values of radioactivity to estimate the isotope concentration in arterial blood. These end-expired data are used as an input function in a mathematical equation to derive rCBF. End-expired air is assumed normally to be in equilibrium with the arterial blood at the alveolar surface of the lung during regular (passive) breathing; this assumption may not be valid during continuous phonation. We therefore have analyzed breathing (inhalation/exhalation) patterns and end-expired radioactivity (133Xe) during (1) speaking, (2) singing, and (3) humming of the national anthem, and also during (4) passive breathing. Statistically significant differences in breathing patterns were measured between a group of nonmusicians and two groups of musicians (singers) during the phonation tasks: The nonmusicians breathed more often (and more rapidly) and exhibited less variability in their breathing patterns than did the musicians. Notwithstanding these differences, the shapes of smoothed functions derived from the end-expired values were not influenced appreciably during phonation (except possibly during talking). The latter finding suggests that estimates of rCBF derived with these data should not be confounded seriously because of the continuous phonation. 相似文献
966.
The ability of prelingually, profoundly deaf readers to access phonological information during reading was investigated in three experiments. The experiments employed a task, developed by Meyer, Schvaneveldt, and Ruddy (1974), in which lexical decision response times (RTs) to orthographically similar rhyming (e.g., WAVE-SAVE) and nortrhyming (e.g., HAVE-CAVE) word pairs were compared with RTs to orthographically and phonologically dissimilar control word pairs. The subjects of the study were deaf college students and hearing college students. In Experiments 1 and 2, in which the nonwords were pronounceable, the deaf subjects, like the hearing subjects, were facilitated in their RTs to rhyming pairs, but not to nonrhyming pairs. In Experiment 3, in which the nonwords were unpronounceable, both deaf and hearing subjects were facilitated in their RTs to both rhyming and nonrhyming pairs, with the facilitation being significantly greater for the rhyming pairs. These results indicate that access to phonological information is possible despite prelingual and profound hearing impairment. As such, they run counter to claims that deaf individuals are limited to the use of visual strategies in reading. Given the impoverished auditory, experience of such readers, these results suggest that the use of phonological information need not be tied to the auditory modality. 相似文献
967.
968.
969.
The interactional teaching strategies of mothers and fathers toward their sociometrically determined popular, moderately popular, or unpopular children, and children's responses to them were examined during a structured puzzle task in a laboratory setting. Parents of popular children used more explanations in aiding their children to complete the puzzle task than parents of moderately popular or unpopular children. Mothers were more likely to offer suggestions, use explanations, and ask questions during the puzzle task than fathers. Analysis of children's responses revealed that popular children were more likely to ignore imperatives by their parents compared with unpopular children, while unpopular children showed a tendency to be more cooperative following imperatives by parents than popular children. Finally, popular children were less likely to ignore but were more likely to go off task following suggestions by parents than either unpopular or moderately popular children. The data are discussed with respect to the possible link between parental socialization patterns and children's popularity in the peer group and the need to consider the interaction patterns in both the peer and parent-child systems for intervention purposes.Portions of this paper were presented by the first author at the Banff International Conference on Behavioral Science, Banff, Alberta, Canada, 1984. The research was supported through the Western Regional Project W144, Development of Social Competencies in Children, with funding from Science and Education Administration/Cooperative Research of the USDA and Utah State University Agricultural Experiment Station. We would like to thank the parents and children for their participation, and Nina Mounts, Maria Norton, Carla Seamons, Soheila Sobhani, and Joan Wareham for their assistance with varying aspects of coding and data analysis. 相似文献
970.
A long-term temporal component of working memory of rats trained on the radial maze has been shown to be susceptible to disruption by the protein synthesis inhibitor, anisomycin. It is not clear whether protein synthesis played a role in working memory because accurate performance on the radial maze required the storage of a large amount of information, or because the information was to be held in store for relatively long periods of time. This experiment tested these hypotheses by assessing the effect of anisomycin on choice accuracy in a comparatively simple spatial delayed alternation task. Results indicate that under the present training conditions, protein involvement in working memory is related more to the length of the retention interval than to the amount of information retained. 相似文献