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This study examines the relationship of social ties and support to patterns of cognitive aging in the MacArthur Studies of Successful Aging (see L. F. Berkman et al., 1993), a cohort study of 1,189 initially high-functioning older adults. Baseline and longitudinal data provide information on initial levels as well as changes in cognitive performance over a 7.5-year period. Linear regression analyses revealed that participants receiving more emotional support had better baseline performance, as did those who were unmarried and those reporting greater conflict with network members. Greater baseline emotional support was also a significant predictor of better cognitive function at the 7.5-year follow-up, controlling for baseline cognitive function and known sociodemographic, behavioral, psychological, and health status predictors of cognitive aging. The findings suggest the potential value of further research on the role of the social environment in protecting against cognitive declines at older ages. 相似文献
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An analysis of student learning with the LISP tutor indicates that while LISP is complex, learning it is simple. The key to factoring out the complexity of LISP is to monitor the learning of the 500 productions in the LISP tutor which describe the programming skill. The learning of these productions follows the power-law learning curve typical of skill acquisition. There is transfer from other programming experience to the extent that this programming experience involves the same productions. Subjects appear to differ only on the general dimensions of how well they acquire the productions and how well they retain the productions. Instructional manipulations such as remediation, content of feedback, and timing of feedback are effective to the extent they give students more practice programming, and explain to students why correct solutions work. 相似文献
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Sensitivity to the pictorial depth cues of shading, linear perspective, and position on the picture plane were investigated with children from 3 to 7 years of age as well as with adults. Using a discriminative learning method, all Ss were found to be sensitive to shading information for depth when the display was oriented vertically, but not when it was oriented horizontally. In addition, binocular view did not decrease sensitivity relative to monocular view. Linear perspective was found to be effective in controlling 3-year-olds’ size discriminations of equal-area figures, while position on the picture plane was ineffective in the absence of other information for depth. 相似文献